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Summary: Due to their gluten‐free dietary needs, celiac patients cannot find bread with the required texture characteristics. The aim of this study was to evaluate the performance of psyllium powder in the production of rice‐based, gluten‐free bread rolls. In this case, five different bread rolls were produced by adding different proportions (0%, 25%, 50%, 75% and 100%) of psyllium powder combinations to bread dough made with rice flour. Moisture and ash content, colour values, volume, symmetry and uniformity indices, textural properties and sensory properties were taken into consideration. It was observed that the addition of psyllium powder gave the bread rolls a spongy structure and decreased the hardness values. As the amount of psyllium powder in the dough formulation increased, darkening in colour and increase in moisture values were observed. In addition, the bread sample psyllium powder and rice flour ratios (1:1) had the largest volume index value (98.67 mm), while the same product received the highest score in SAW techniques. [ABSTRACT FROM AUTHOR]

The development of SAW transducers requires a series of steps ranging from material selection and geometry design to the selection of fabrication techniques for their characterization and validation process. Here, we use the finite element method (FEM) to present a methodology and a detailed analysis of the design of SAW transducers in a delay line configuration. First, we simulate single‐finger and double‐finger configurations with different geometries and designs of IDTs on two piezoelectric substrates, LiNbO3$$ {}_3 $$ in 64°$$ {}^{{}^{\circ}} $$ YX and LiNbO3$$ {}_3 $$ 128°$$ {}^{{}^{\circ}} $$ YX orientation, to compare the simulation results with the analytical delta model and thereby validate the simulation process, presenting Root Mean Square Error (RMSE) values ranging from 10.79 dB to 16.42 dB. With the above, we performed a comparative analysis to determine the influence of piezoelectric material and IDT configuration by studying a specific transducer design made to operate at a resonance frequency of 97.02 MHz. We compared identical designs on 128°$$ {}^{{}^{\circ}} $$ YX and 64°$$ {}^{{}^{\circ}} $$ YX orientations of LiNbO3$$ {}_3 $$ with single and double‐finger configurations and added the comparison with the SPUDT configuration. We observed the best results for the single‐finger IDT configuration in 128°$$ {}^{{}^{\circ}} $$ YX LiNbO3$$ {}_3 $$ orientation compared to the other variants through its insertion loss level of −7.29 dB, its average sidelobe level of −18.63 dB, and its average transition band slope for the main lobe of 15.09 dB/MHz. The results guide new researchers or students in expanding the use of numerical tools in designing SAW transducers and SAW devices. [ABSTRACT FROM AUTHOR]

GHz operating single port SAW resonators have been manufactured on Sc0.3Al0.7N/Si substrate. The thickness of the ScAlN thin layer was 0.8 μm. Advanced nano‐lithographic techniques have been developed for devices manufacturing. Rayleigh and Sezawa modes have been evidenced on Sc0.3Al0.7N/Si structure. The targeted applications are temperature sensors for harsh environmental operations. The sensitivity and temperature coefficient of frequency (TCF) of the manufactured devices have been experimentally determined and analyzed. The mode shapes of the resonances that appear in the devices supported on Sc0.3Al0.7N/Si substrate were evidenced by finite element method (FEM) simulations. A technique that combines FEM with Coupling of Modes (COM) was used for the determination of the resonance frequencies. Simulations performed for the temperature dependence of the resonance frequency led to results close to the experimental ones for the Rayleigh mode as well as for the Sezawa mode for devices supported on Sc0.3Al0.7N/Si substrate. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

GHz operating single port SAW resonators have been manufactured on Sc0.3Al0.7N/Si substrate. The thickness of the ScAlN thin layer was 0.8 μm. Advanced nano‐lithographic techniques have been developed for devices manufacturing. Rayleigh and Sezawa modes have been evidenced on Sc0.3Al0.7N/Si structure. The targeted applications are temperature sensors for harsh environmental operations. The sensitivity and temperature coefficient of frequency (TCF) of the manufactured devices have been experimentally determined and analyzed. The mode shapes of the resonances that appear in the devices supported on Sc0.3Al0.7N/Si substrate were evidenced by finite element method (FEM) simulations. A technique that combines FEM with Coupling of Modes (COM) was used for the determination of the resonance frequencies. Simulations performed for the temperature dependence of the resonance frequency led to results close to the experimental ones for the Rayleigh mode as well as for the Sezawa mode for devices supported on Sc0.3Al0.7N/Si substrate. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Recently Lamb wave devices have originated as an alternate acoustic device for high‐frequency wireless sensing applications. Their potential for sensing devices, including biomedical diagnostics and environmental monitoring as a wireless and passive device, calls for further analysis of the device with higher sensitivity. ZnO‐based sensor has always been of research interest due to its biocompatibility, sensing abilities, and yet cost‐effectivity. A Lamb wave device based on ZnO/SiO2/Si membrane has been theoretically simulated using finite element analysis method (FEM) to study the higher modes, as higher working frequency leads to higher sensitivity of the device toward sensing applications. Optimized properties are identified and utilized for the fabrication of Lamb wave devices. It is observed that for optimized parameters of ZnO/SiO2/Si Lamb device, higher antisymmetric modes are not only advantageous for high sensitivity applications but also more stable within the given operating conditions. Experimentally obtained results indicate close matching with theoretical results. [ABSTRACT FROM AUTHOR]

For the application of surface acoustic wave sensors at high temperatures, both a high‐temperature stable piezoelectric substrate and a suitable metallization for the electrodes are needed. Our current attempt is to use TiAl thin films as metallization because this material is also known to be high temperature stable. In this study, Ti/Al multilayers and Ti‐Al alloy layers were prepared in combination with an SiO2 cover layer or a W barrier layer at the interface to the substrate (thermally oxidized Si or Ca3TaGa3Si2O14) as an oxidation protection. To form the high‐temperature stable γ‐TiAl phase and to test the thermal stability of the layer systems, thermal treatments were done in vacuum at several temperatures. We used X‐ray photoelectron spectroscopy (XPS) sputter depth‐profiling to investigate the film composition and oxidation behavior. In this paper, we demonstrate how the semiautomatic peak fitting can help to extract beside the elemental information also the chemical information from the measured depth profiles. [ABSTRACT FROM AUTHOR]

Aim: Oral and maxillofacial surgeons typically spend over 20 h in the operating theatre every week. Many of their procedures involve the use of powered bone and tooth cutting devices, which generate potentially harmful levels of noise. Prolonged exposure to loud noises is associated with hearing loss, increased serum cortisol levels, detrimental cardiovascular outcomes, and poor task performance. This study explores the noise generation of common powered tooth and bone cutting devices in a theatre setting. Materials and methods: Both compressed air and electric devices were tested. For compressed air devices three burs were tested – jet, round and fissure. Results: The study found that at the proximity of the patient and surgeon, all tested devices generated noise above the safe threshold of 75 decibels. At the distance of 1 m or more (corresponding to the anaesthetist and scout nursing staff), the Surgairtome and oscillating saw were the only powered osteotomy devices below the safe noise level. Conclusions: This study explores the impact of noise generation from powered osteotomy devices. This may have health implications for theatre staff, the surgeon, anaesthetist, and the patient. [ABSTRACT FROM AUTHOR]

Excessive power supply noise (PSN) such as IR drop can cause yield loss when testing very large scale integration chips. However, simulation of circuit timing with PSN is not an easy task. In this study, the authors predict circuit timing for all test patterns using three machine learning techniques, neural network (NN), support vector regression (SVR), and least‐square boosting (LSBoost). To reduce the huge dimension of raw data, they propose four feature extractions: input/output transition (IOT), flip‐flop transition in window (FFTW), switching activity in window (SAW), and terminal FF transition of long paths (PATH). SAW and FFTW are physical‐aware features while PATH is a timing‐aware feature. Their experimental results on leon3mp benchmark circuit (638 K gates, 2 K test patterns) show that, compared with the simple IOT method, SAW effectively reduced the dimension by up to 472 times, without significant impact on prediction accuracy [correlation coefficient = 0.79]. Their results show that NN has best prediction accuracy and SVR has the least under‐prediction. LSBoost uses the least memory. The proposed method is more than six orders of magnitude faster than traditional circuit simulation tools. [ABSTRACT FROM AUTHOR]

SUMMARY A wireless node of strain sensor was developed for structural health monitoring. Surface acoustic wave oscillators were used as sensor heads of the system, and can linearly detect the strain of 10−5 to 10−6 order. In the developed sensor node, a mixer chip and communicator were integrated on the board for temperature compensation and construction of sensor mesh network. We practically applied the developed sensor nodes to measurement of the static deformation in the metal plate, and successfully detected the deformation distribution. In this experiment, power consumption of each node was 190 μW in sleep mode and 50 mW in data transmission mode. [ABSTRACT FROM AUTHOR]

Modern surface-acoustic-wave devices are characterised by their trend to higher frequencies, power densities, and new applications. For this, a shrinking of the dimensions is necessary but hardly possible to achieve with standard Al-based metallisation because of increased stress-induced damaging (acoustomigration). In this context additional barrier interlayers between substrates and electrodes are necessary, especially for high-temperature applications. For this, we present results of a detailed chemical interface analysis of deposited Ta and Ti thin-film growth onto surface acoustic wave-substrate materials (LiNbO3 and LiTaO3) with respect to their interface layer structure and its temporal and thermal stability in vacuum. The analysis was mainly performed using non-destructive and surface sensitive angle-resolved X-ray photoelectron spectroscopy. Besides a slight oxidation (oxygen adsorption) at the surface of these highly reactive metal thin films all interface sequences are stable up to 24 h. We also report higher thermal stability of Ta thin films up to 600 °C in contrast to Ti thin films (300 °C) because of presumed diffusion of Ti along grain boundaries. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study presents a technique to identify current transformer (CT) saturation based on waveshape properties of the CT secondary current. First, a variable‐length window, designated as the symmetry assessment window (SAW), is defined. Certain distinctive features of the distorted and undistorted currents inside the SAW are extracted by defining two variance functions. Using the extracted features, a new criterion is introduced to detect CT saturation. The proposed method is unaffected by fault current characteristics and CT variable parameters, such as CT burden, core remanence and its magnetising curve. One major contribution of this method is allowing cheaper measurement systems for busbar protection by easing the relay CT requirements. Analysis of real power system fault currents in a real‐time manner using a hardware setup is accompanied by PSCAD/EMTDC simulation results to verify the accuracy and high speed of the proposed technique in various conditions. [ABSTRACT FROM AUTHOR]

Network selection mechanisms have a significant role in guaranteeing the QoS for users in a heterogeneous wireless networks environment. These mechanisms allow the selection of an optimal wireless network to satisfy the needs of users. Users are provided with the opportunity to select from multiple connectivity opportunities available all over various wireless networks. Furthermore, the network operators themselves can execute active selection strategies that facilitate proper decision making, in which user preferences are considered. This study proposes a new noncooperative competing game-theoretic model and strategy space based on user preference. This model can solve network selection problems and capture the inter-linkages of decisions taken by various networks. A generalized simple additive weighting method is incorporated into the framework of noncooperative game theory. In addition, the utility function is employed to assess the usefulness of the system. Simulation results and analysis illustrate the efficacy of the suggested model in attaining optimum network utility for heterogeneous wireless networks while optimizing user satisfaction. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

For surface acoustic wave devices, piezoelectric substrates have to be coated with barrier and metallization layers. The interface formation plays an important role for the functionality of the layer systems. We used angle-resolved XPS for nondestructive interface characterization of such material systems. However, the analyses are challenging for complex systems as considered here, because model calculations always have to be performed for data interpretation. To eliminate measuring uncertainties, in a first step, Monte Carlo simulations of angle-resolved XPS measurement were performed. By use of such reliable data, system inherent uncertainties can be revealed. It is shown that the application of appropriate boundary conditions is inevitable the more complex the structures are. The use of high (near-surface) measuring angles is discussed as one possible advantageous way. [ABSTRACT FROM AUTHOR]

Next generation surface acoustic wave (SAW) devices require improved metallisations due to the demand of higher frequencies and power densities for new applications. Most likely, these metallisations will include adhesion or diffusion-barrier layers between the piezoelectric substrate and the electrode. For improved properties, the pre-treatment of the substrate and the chemical state of these layers is of great interest. This work gives an overview about studies of the effect of surface preparation at LiNbO3 substrates for Ta and Ti depositions and their different chemical reactions (oxidation) with the substrate surface. An ion beam and a radio-frequency plasma source are applied for surface treatment; a dicrect current (DC)-sputter process is used for the deposition. The characterisation of the surface's chemical changes is performed by XPS connected to a separate preparation chamber (quasi in situ) used for pre-cleaning and film deposition. The detailed chemical layer structures at the surfaces are determined by angle-resolved XPS and comparison with model calculations. In addition, atomic force microscope measurements are used to study the surface morphology showing almost no difference in surface roughness of the preparations. [ABSTRACT FROM AUTHOR]

Projected capacitive (p-cap) touch technology now dominates the consumer-electronics touch market, but many different touch technologies still compete in the commercial touch applications. Why is this so? Will it continue? While p-cap market share will continue to grow, this objective analysis supports the view that diverse requirements in commercial-touch applications will maintain touch 'biodiversity'. [ABSTRACT FROM AUTHOR]

Aluminum nitride (AlN) based high frequency surface acoustic wave (SAW) devices are produced by using a new CMOS compatible concept. Textured c-axis oriented AlN films have been deposited on tungsten based embedded interdigital transducers (IDTs) by the reactive pulse DC-sputter technique within the thermal budget of back end of line (BEOL) processes. Two SAW Rayleigh modes with different acoustic velocities were measured and identified by finite element method (FEM) simulation (Kaletta and Wenger, FEM Simulation of Rayleigh waves for CMOS compatible SAW devices based on AlN/SiO2/Si(100) (Elsevier Ultrasonics, available online 18 April 2013, ISSN 0041-624X, 10.1016/j.ultras.2013.04.009) [1]). Electromagnetic crosstalk between in- and output IDTs via low resistive Silicon substrates is one of the most troublesome sources of integrated SAW devices. The impact of several device parameters like the acoustic aperture, the number of fingers and the delay line length on the electromagnetic crosstalk was studied and routes for optimizing SAW filter designs on low resistive Si(100) will be presented. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Simulations using a combination of the finite-element method and the analytical method as well as experiments are used to study new-mode-type SAWs. First, in 171°YZé-LiNbO3, it is found that there exists a longitudinal leaky SAW with a high acoustic velocity and a high Q in a grating structure with an Al film thickness of 0.084 wavelength. The acoustic velocity is 6100 to 6500 m/s and the Q values are more than 4000 (computed) at both the resonance and antiresonance points. These excellent properties are suitable for high-frequency SAW devices. Next, in 15°YX-LiNbO3, it is found that there exists a grating mode SAW of a transverse wave type in a grating structure with an Al film thickness of 0.125 wavelength. In this case, k2 has an extremely large value of 28.5% and hence the mode is suitable for a SAW resonator for use in a voltage-controlled oscillator. By means of this SAW, SAW-VCOs at 400 and 170 MHz for mobile communication are fabricated. At 400 MHz, the frequency variable width is 54 MHz (3.2%/V) and the phase noise is less than –115 dBc/Hz at 25 kHz; the corresponding values at 170 MHz are 24 MHz (3.4%/V) and < –12 dBc/Hz at 25 kHz. © 2001 Scripta Technica, Electron Comm Jpn Pt 2, 84(4): 49–58, 2001 [ABSTRACT FROM AUTHOR]

It was found that the surface acoustic wave (SAW) amplitudes in SAW filters made of ZnO films vary from filter to filter even when the center frequencies are the same and the deviation of amplitudes must be reduced. It was found also that the frequency and amplitude characteristics could be improved by mirror polishing of the ZnO film surface. In an SAW filter with a ZnO/interdigital transducer (IDT)/glass substrate structure, periodic convex areas due to the thickness of the finger electrode of IDT and fine roughness were present on the device surface. As a result of investigating the influence of the surface structure on the amplitude deviation, it was found that the convex areas did not influence the electromechanical coupling coefficient; but they reduced the acoustic velocity of SAW. In addition, it was clarified that the convex areas due to the finger electrode and fine roughness on the ZnO surface caused deviations in the acoustic velocity of SAW and reflections of SAW, causing a deviation in the amplitude characteristics. [ABSTRACT FROM AUTHOR]

The formation of ZnO piezoelectric films has been attempted using the electron cyclotron resonance (ECR) sputtering system. It has been confirmed that this system is capable of depositing a ZnO piezoelectric film with a specific resistance of 1010 - 1011 Ω · cm and c-axis orientation with a standard deviation of σ = 0.19° on an IDT (comb-shaped electrode)/glass substrate at a low temperature (no substrate heating ∼200°C) and low gas pressure (∼10-4 torr). It has been clarified that SAW devices using these ZnO films exhibit good SAW characteristics (particularly distinct at the high-frequency band) and a good electromechanical coupling factor (94 percent of finite element method (FEM) theoretical value with single electrode) compared to ZnO films deposited by a conventional sputtering method. In a ZnO film deposited without substrate heating, a SAW basic wave has been excited for the first time. [ABSTRACT FROM AUTHOR]

This paper considers the characterization of surface skimming waves (SSBW) by two newly defined parameters, i.e., effective electromechanical coupling factor and critical length. The parameters are estimating easily by the effective permittivity and are directly applicable to the delta function model analysis. Experiments on a TVIF SAW filter agreed well with the analysis. In addition, these parameters for SO2/36° YX-LiTaO3 structure were estimated. It is shown both theoretically and experimentally that the SSBW responses can be suppressed by depositing SiO4 with appropriate thickness. [ABSTRACT FROM AUTHOR]

We reported that zinc oxide (ZnO) films deposited by direct current (DC)-mole electrocyclotron resonance (ECR) and radio frequency (RF)-mode ECR sputtering systems had shown excellent piezoelectric properties and c-axis orientations. The RF-mode ECR sputtering system was capable of depositing ZnO films on glass substrates without evidence of column and fiber grains in crosssection analysis white driving a 1.1-GHz fundamental Rayleigh surface acoustic wave (SAW). In this paper, we investigate the properties of ZnO film deposited by an RF-magnetron-mode ECR sputtering system which has added magnets to the outside of a cylindrical zinc metal (Zn) target of the RF-mode ECR sputtering system. The ZnO film on the glass substrate deposited by this system was capable of driving a 1.3-GHz fundamental Rayleigh SAW. This shows a higher frequency than the previously reported ZnO film. This film exhibits most of the same effective electromechanical coupling factors (keff) as the theoretical keff values calculated by finite-element method (FEM) using the constants of ZnO single crystal (that is, 97 percent of theoretical value) and 0.6 ∼ 3.6 dB lower insertion loss in comparison with the films deposited by the DC-mode ECR and the RF-mode ECR. A (1120) plane epitaxial ZnO film was deposited at low temperatures on an R-plane sapphire substrate using this system and was capable of driving a 2.34-6Hz Sezawa wave. By measuring the photoluminescence property of a thin, 1.2- μm, epitaxial ZnO film, free exitons are observed for the first time. [ABSTRACT FROM AUTHOR]

A surface acoustic wave (SAW) electrostatic voltage sensor was fabricated using an SAW oscillator. In the electrostatic voltage sensor, the electrodes to apply electrostatic voltage and produce strain by piezoeffect are not located on the top and bottom surfaces of the sub-state but rather on the propagation surface in parallel to the propagation path. Therefore, it is possible to reduce the gap spacing between the electrodes to apply an electrostatic voltage so that the sensitivity can be improved. When an electrostatic voltage is applied, the LiNbO3 single crystal and PZT ceramic were used as substrates in this experiment. The most sensitive crystal plane in a rotated Y-X plate rotating about the X axis was obtained for LiNbO3single crystal. It was found the result shows that the 90° rotation Y-X plate is the best. In the experiment, a 131° rotation Y-X plate with 20 × 25 × 1.0 mm³ was used which is close to the derived angle and is obtained easily. The interdigital transducer (IDT) electrodes and the electrodes for applying electrostatic voltage were fabricated by Al evaporation. The characteristics of the oscillation frequency versus electrostatic voltage of the sensors were studied. The sensitivity was 0.133 Hz/V and 0.03 Hz/V for the 131° rotation Y-X plate and a Y-X plate in the case of LiNbO3. In the case of PZT ceramic, the sensitivity was 12 Hz/V. The dependence of the sensitivity on gap distance between the electrodes for applying electrostatic voltage and on temperature was also studied. [ABSTRACT FROM AUTHOR]

Summary: The aim of the current research is to develop a more accurate Web service selection approach that can deal with value constraints on QoS criteria in the user request. The purpose is to be able to promote services even when all the value constraints are not satisfied and hence rank them according to their closeness to meet the latter. For this effect, we use MCDM (Multi Criteria Decision making) methods together with suitable normalization techniques at different stages of the process. First of all, we consider an extension of the AHP method to compute and normalize the weights associated with the QoS criteria considered in the Web service selection. Second, we introduce a more consistent normalization technique, called OMRI, to normalize data according to value constraints. Third, we propose to extend different ranking MCDM methods to the OMRI normalization so that it becomes possible for them to cope with value constraints. The considered methods are SAW, TOPSIS, VIKOR, and WPM. To compare the accuracy of the extended ranking methods, we use the Borda compromise solution together with different similarity ratios. To validate the solution, several experiments have been conducted on a real dataset as well as on an artificial one. [ABSTRACT FROM AUTHOR]