Top PDF Method of ultrasonic measurement of texture

Method of ultrasonic measurement of texture

Method of ultrasonic measurement of texture

A method for measuring texture of metal plates or sheets using non-destructiveultrasonic investigation includes measuring the velocity of ultrasonic energy waves in lower order plate modes in one or more directions, and measuring phase velocity dispersion of higher order modes of the plate or sheet if needed. Textureor preferred grain orientation can be derived from these measurements with improves reliability and accuracy. The method can be utilized in production on moving metal plate or sheet.

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Method of ultrasonic measurement of texture

Method of ultrasonic measurement of texture

A method for measuring texture of metal plates or sheets using non-destructive ultrasonic investigation includes measuring the velocity of ultrasonic energy waves in lower order plate modes in one or more directions, and measuring phase velocity dispersion of higher order modes of the plate or sheet if needed. Texture or preferred grain orientation can be derived from these measurements with improves reliability and accuracy. The method can be utilized in production on moving metal plate or sheet.

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Adaptive Texture Energy Measure Method

Adaptive Texture Energy Measure Method

The texture was defined as a regular repetition of an element or a pattern [1] where a contiguous set of pixels with some tonal and/or regional property to provide infor- mation such as brightness, color, shape, size, etc [2]. Tex- ture analysis has been used for recognizing or classifying objects, finding edges, shapes, etc. Texture methods was classified into three sub-groups: spectral methods trans- forms image into Fourier domain to detect global periodic- ity by identifying high energy, narrow peaks, statistical methods, analysis pixel-by-pixel relations and structural methods use properties of primitives and their placement. However, a major problem with this kind of applications is determining best suitable texture analysis method that in- creases meaningful of the image. A variety of methods are
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Semi automatic system for ultrasonic measurement of texture

Semi automatic system for ultrasonic measurement of texture

A means and method for ultrasonic measurement of texture non-destructively and efficiently. Texture characteristics are derived by transmitting ultrasound energy into the material, measuring the time it takes to be received by ultrasound receiving means, and calculating velocity of the ultrasound energy from the timed measurements. Textured characteristics can then be derived from the velocity calculations. One or more sets of ultrasound transmitters and receivers are utilized to derive velocity measurements in different angular orientations through the material and in different ultrasound modes. An ultrasound transmitter is utilized to direct ultrasound energy to the material and one or more ultrasound receivers are utilized to receive the same. The receivers are at a predetermined fixed distance from the transmitter. A control means is utilized to control transmission of the ultrasound, and a processing means derives timing, calculation of velocity and derivation of texture characteristics.
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Ultrasonic Measurement of Texture of Cubic and Hexagonal Materials

Ultrasonic Measurement of Texture of Cubic and Hexagonal Materials

However, W400 must be determined from absolute measurements of So or SHo wave velocities, hence the errors associated with the estimates are larger compared to those ofW420 and W440· A c[r]

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Analysis of a Semi Automatic System for the Ultrasonic Measurement of Texture

Analysis of a Semi Automatic System for the Ultrasonic Measurement of Texture

Comparison to evaluation of the systematic errors between ultrasonic and diffraction determinations of ODC's establish that the accuracy of the semi-automatic system does not limit the i[r]

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Means and method for ultrasonic measurement of material properties

Means and method for ultrasonic measurement of material properties

The system for field measurement of texture, stress and related material properties such as formability parameters using ultrasonic velocity measurements through crystalline plate or sheet. Electromagnetic acoustic transducers are utilized to generate, transmit, and receive ultrasonic bursts through the plate at different angular orientations with respect to the plane of the plate. Two of the transducers are driven in series when generating the ultrasonic bursts. Time measurements between transmission and reception of the bursts are precisely derived and converted into velocities. Information regarding stress, texture, and other related material properties such as formability parameters can be derived from these velocity measurements. The system is adjustable to be used for both ferrous and nonferrous crystalline plate. Alteration of the types of ultrasonic waves utilized, and the methods of generating the waves allows different properties such as texture and stress to be derived.
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Annular arrays for novel ultrasonic measurement techniques

Annular arrays for novel ultrasonic measurement techniques

Received: 29 April 2016 – Revised: 30 August 2016 – Accepted: 22 September 2016 – Published: 1 November 2016 Abstract. The paper shows how the precise knowledge of the sound field of an ultrasonic annular array can con- tribute to the development of novel measurement techniques. Emphasis is placed on (a) a non-invasive method for sound velocity measurements in fluids using the echo signals from scattering p]articles, (b) a non-invasive method for the combined determination of thickness and sound velocity in layered structures by using a novel fo- cusing technique, and (c) a non-scanning curvature measurement method exploiting the wave front curvature of a reflected wave. To demonstrate the methods, the principles as well as results of simulations and measurements are discussed.
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A Portable Ultrasonic Bone Densitometer For The Measurement Of Multiple Sites

A Portable Ultrasonic Bone Densitometer For The Measurement Of Multiple Sites

Currently, dual-energy X-ray absorptiometry (DEXA) is the most commonly used technique for assessment of bone status and is considered the ‘‘gold standard’’ reference for measuring bone mineral density (BMD, g/cm 2 ) [2, 3]. However, DEXA cannot be employed for population mass screenings due to its high cost, inconvenience, and reticence among patients concerning X-ray exposure[4]. This has led to increasing interest in the research of quantitative ultrasound (QUS) methods for evaluating bone status purposes [5-7]. QUS was considered to reduce the medical and economic burden of this disease, provided that cost-effective strategies for identifying patients at high risk for fracture. In addition, QUS seems to provide information not only about BMD but also about the microarchitecture and elasticity of bone[8, 9], so it becomes a promising method of bone status assessment. At present, in commercial devices, QUS methods are usually categorized into two classes of methods: (a) through-transmission techniques in which the ultrasound wave passes through bone, e.g. heel bone, and the (b) axial-transmission techniques in which the ultrasound wave propagates along the long axis of bone, such as the radius or the tibia [10-12]. The parameters of ultrasonic measurement are: (a) through-transmission: broadband ultrasonic attenuation (BUA) and speed of sound at the calcaneus (SOS), (b) axial-transmission: speed of sound of the first arriving signal (SOS FAS ) [10]. Clinical results have shown that QUS parameters (BUA, SOS,
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Propagation of measurement uncertainty for surface texture parameters

Propagation of measurement uncertainty for surface texture parameters

A method using a Bayesian approach will also allow certain prior rules to be observed that could be overlooked using an analytical approach. In the case of an ultra flat surface, the magnitude of a parameter value could be overshadowed by that of the associated uncertainty. Figure 3 shows such a case where the probability density function (PDF) of the calculated Ra value crosses over the zero threshold. Therefore, when determining a coverage interval for a parameter, it could lead to the belief that the parameter has a finite probability of being negative or taking some other infeasible value. A Bayesian method would not allow this as part of the prior knowledge would simply state that this value cannot be negative.
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Effect of zooming on texture features of ultrasonic images

Effect of zooming on texture features of ultrasonic images

Eighteen images of carotid plaques producing stenosis greater than 50% were included in this study. These were obtained from consecutive asymptomatic patients, partic- ipants of the Asymptomatic Carotid Stenosis and Risk of Stroke (ACSRS) multicenter natural history study [18]. Stenosis severity was estimated with velocity ratios (Euro- pean Carotid Surgery Trial – ECST – method), as previ- ously described [19], using an ATL HDI 3000 scanner (Philips Medical Systems, Bothell, WA, USA). A linear post-processing curve was used during carotid scanning, B-mode and colour-coded still images (Figures 1 and 2) were stored on magneto-optical disks as Tagged Image File Format (TIFF) files [resolution of 576 pixels (height) × 768 pixels (width)]; the same still (frozen) B-mode
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Comparison of Type F2 Software Measurement Standards for Surface Texture

Comparison of Type F2 Software Measurement Standards for Surface Texture

The mean line is a base to which feature parameters are referred. Unfortunately, most of the mean line crossing-points are excluded in the measured data point set, and the position of a mean line crossing-point is generally estimated from its neighbouring points. Thus, there are many different algorithms to estimate a crossing-point and the method uncertainty is introduced to the final results. In addition, there is error when calculation based on the measuring data point set without those mean line crossing-points [43]. Brennan recommended the need to include implied mean line crossing points simply by interpolating the data where these occur and provide each profile peak or valley element with calculated boundary values.
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INSTRUMENTAL TEXTURE MEASUREMENT OF MEAT IN A LABORATORY RESEARCH AND ON A PRODUCTION LINE

INSTRUMENTAL TEXTURE MEASUREMENT OF MEAT IN A LABORATORY RESEARCH AND ON A PRODUCTION LINE

The most commonly used test to determine the texture in laboratories around the world are the methods which use testing or strength test- ing machines with appropriate instrumentation. The most frequently used measurement sensors are Warner-Bratzler blade (WB) and the Kramer cell. The principle of the methods is based on the simulation of chewing food products. The first idea of cutting test, conducted using samples of cooked meat, was developed in 1920 by Kenneth F. Warner and colleagues to measure the fragility [22]. The method using a Warner-Bratzler’s blade was developed in 1932 by Lyman J. Bratzler and since the 1950’s it is widely used to determine the tenderness of meat products, fish and cakes. U.S. scientists, through multicenter studies, cre- ated a definite procedure to deal with samples and pointed the test conditions, so that the WB test conducted in accordance with the proto- col allows for direct comparison. This method applied in case of meat samples, require flat, V-shaped blade (thickness of 0.04 inches, the angle of the blade 60º, the speed of the working element 200–500 mm/min) (Fig. 1). In addition, the sample should be characterized by diameter of half an inch and be conducted with the cutting blade configured perpendicularly to the direction of muscle fibres [21].
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Flow velocity measurement using a spatial averaging method with two dimensional flexural ultrasonic array technology

Flow velocity measurement using a spatial averaging method with two dimensional flexural ultrasonic array technology

extracted by two-dimensional flexural array technology. A two-dimensional flexural ultrasonic array transducer was used to conduct flow measurements in a commercial flow rig, utilizing a calibrated mechanical flow meter as a reference. The array transducer comprised eight individual elements positioned in a 2 × 4 configuration, arranged symmetrically around the diametral plane of a custom meter body. This array transducer was operated together with a single ultrasonic transducer, forming eight ultrasonic paths in two chordal planes, symmetric and adjacent to the diametral plane, and measured flow velocities, independently utilizing the classical ultrasonic transit-time flow measurement method. The flow rate was adjusted from 0 to 2500 m 3 /h in steps of 100 m 3 /h, and the average flow velocity over the cross-section of the meter body was thus measured through the eight ultrasonic paths. Fluctuations in measurement were detected around the reference velocity for all eight ultrasonic paths, with RMS deviations ranging from 3.65% to 8.87%, with an average RMS deviation of approximately 6.90%. The spatial averaging method was then implemented on the eight ultrasonic paths as a whole, where the RMS deviation was determined to have reduced to 2.94%. The spatial averaging method was shown to substantially reduce the influence of the fluctuations in flow velocity. Furthermore, the symmetry of the two-dimensional array transducer renders the measurements less susceptible to inaccuracy due to the circumferential flow. Unlike conventional single ultrasonic transducers, which typically form only one single ultrasonic path in a diametral or a chordal plane of a pipe, two-dimensional flexural ultrasonic array technology enables flow velocity to be more accurately measured through multiple adjacent ultrasonic paths in the same plane or two symmetric planes, lowering the uncertainty of measurement. This research is beneficial for both single-path and multi-path ultrasonic flow meters, which typically assign only one ultrasonic or two symmetric paths to each plane of interest. Optimization of the structure and the parameters of the two-dimensional flexural ultrasonic array transducer is possible to further improve the measurement accuracy, provided that the spatial averaging method is properly implemented.
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Ultrasonic Method for Testing Spot Welds

Ultrasonic Method for Testing Spot Welds

Figure 9 shows examples of B-scope representation using the signal received in the abovementioned 31 paths. The horizontal axis is the time and the vertical axis is the ultrasound path shown in Fig. 6(a). As shown in Fig. 9, in the sample with a reference diameter of zero, the time difference between the through-transmitted wave along the center path and the through-transmitted wave along the side path is very short, because there is no weld metal to change the ultrasound velocity. On the contrary, in the sample with a large reference diameter, the time difference between the through-transmitted wave along the center path and the through-transmitted wave along the side path is long. Namely, the nugget diameter measured by attenuation measurement can be compensated by using the transit time measurement result. The path where the transit time of the Receiving
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Application of a Methodology for Measuring Aerospace Parts by Ultrasonic Considering the Measurement Uncertainty through Analytical and Monte Carlo Simulation Method

Application of a Methodology for Measuring Aerospace Parts by Ultrasonic Considering the Measurement Uncertainty through Analytical and Monte Carlo Simulation Method

The Corrosion is a major enemy of aircraft maintenance, since it reduces the structural member integrity and, if not corrected in time, may result in loss of member and flight safety. The general procedure of corrosion removal in structural members consists in identifying the affected member thru aircraft maintenance manuals, removing the damage using a proper procedure, visually inspecting and performing nondestructive inspections. One of the nondestructive tests carried out is the thickness measurement of a structural affected member. The evaluation of remaining static and fatigue strength of the affected part is performed by comparing the minimum remaining thickness with the allowable limits as stated in the aircraft technical manuals. In the above mentioned procedure, the steps related to remaining thickness measurement by ultrasonic testing and results assessment are the critical steps. They require extreme care since can contain several errors coming from not estimated uncertainties of the measurement procedure, resulting in a wrong decision by technician or engineer. If the measurement does not occur with reliability, the actions to be taken may be completely wrong, affecting the flight safety an d increasing the industry costs substantially. In this case, it is necessary the establishment of criteria in order to ensure the metrological confidence. This is the goal of the method proposed in this work.
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Development of evaluation method of residual stress measurement for gear tooth root based on ultrasonic actuation by piezoelectric wafer

Development of evaluation method of residual stress measurement for gear tooth root based on ultrasonic actuation by piezoelectric wafer

Gears are widely used as machine transmission parts to transfer power and change the speed and direction of rotation. The main failure modes of the gear are broken teeth and tooth surface wear, caused mainly by large residual stress. Traditional inspection methods, such as X-rays, cannot measure tooth root residual stress accurately due to the special structure of the tooth root. In this paper, an ultrasonic method involving the longitudinally critically refracted (L CR ) wave was used to measure the gear tooth root residual stress. The special
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The real-time measurement of wear using ultrasonic reflectometry

The real-time measurement of wear using ultrasonic reflectometry

Drawbacks in the initial measurement method are introduced from temperature effects in the form of thermal expansion and variations in the acoustic velocity of the material. Introducing a reference reflection can reduce this error, but various assumptions have been made such as a linear temperature gradient across the pin. Using a more realistic exponential thermal gradient would yield more accurate results. Variations can be seen between the different measurement techniques. The mass lost measurement does not consider displaced material on the pin, resulting in an under estimation of wear volume. For the aluminium and steel combination, this was a considerable effect. The thickness measurements using the digital calipers measures the thickest part of the pin and the ultrasonic measurements measure the average pin thickness over the sensor aperture. The LVDT is a traditional real-time wear measurement system, but the accuracy of the results is highly dependent on the experimental set-up. During the test, some material was transferred to the disk in which would result in an underestimation of pin wear volume as this would reduce the measured displacement. It is difficult to draw direct comparison as each method is measuring something different.
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The repeatability and reproducibility of gingival thickness measurement with an ultrasonic device

The repeatability and reproducibility of gingival thickness measurement with an ultrasonic device

thane surface resembling the gingiva; on each of  these points, the thickness was measured with an ultrasound method and an invasive method using an endodontic K-file, with individual measurements taken directly. An optical microscope was used to calculate the thickness of  the polyurethane based on the direct method. In ex- perimental conditions using an ultrasound and transgin- gival probing method, 10 measurements of the GT of the swine maxilla were taken at each of 4 GT1 points (midway through the keratinized gingiva) and 4 GT2 points (2 mm apically from the mucogingival junction). Measurements of the thickness of polyurethane by means of 3 methods produced results that were very similar to one another. However, the greatest inaccuracies when compared to di- rect measurements occurred with the invasive method. Most of the GT values measured on the swine mandible using the invasive method were higher than the values re- corded with ultrasonography. The greatest inaccuracies recorded with the ultrasound method concerned mea- surements of the mobile mucosa in one of the GT2 points, and amounted to 10.3%. The data obtained in clinical conditions are confirmed by the occurrence of  smaller measuring deviations noted with ultrasound biometrics compared with the invasive method.
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Precision Core Temperature Measurement of Metals Using an Ultrasonic Phase-Shift Method

Precision Core Temperature Measurement of Metals Using an Ultrasonic Phase-Shift Method

One of the temperature measurement methods for workpieces reported in literature is the tool/workpiece thermocouple [4–6]. The main difficulties reported concerning the use of this method are the parasitic electromotive force (EMF) from secondary joints, the necessity for the accurate calibration of the tool and workpiece as a thermocouple pair, the need to isolate the thermocouple from the environment and the lack of clarity on what the EMF represents [5,6]. Also, this method does not indicate the core temperature of the workpiece. Infrared thermometry is another method that has been used in both dry conditions and with the presence of coolant [7]. However, the measurement only represents the surface temperature, and the accuracy that can be achieved with this method is less than the required accuracy for the precision machining of some materials, as infrared cameras’ stated accuracy is typically ± 2 ◦ C [8]. Moreover, this value is only valid in ideal conditions, as the accuracy will greatly reduce in harsh machining environments. Infrared cameras also require a good line of sight to work. Of all the methods previously used, none gives a direct indication of the core temperature of the workpiece, which is the parameter that affects the dimensional expansion.
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