Factors influencing intention to purchase through VR platforms

With technological advancement, Virtual Reality (VR) significantly impacts various industrial sectors, including education, medicine, gaming, and tourism. In particular, the idea of VR has been extensively applied in e-commerce to create realistic online shopping experiences. The purpose of this study is to investigate factors influencing purchase intention through VR platforms by applying the concept of the IS success model and flow theory. The data were collected from 300 respondents with experience in online shopping via e-commerce websites. Confirmatory factor analysis and structural equation modeling were used to test the proposed research model. Results indicate that factors influencing purchase intention through virtual reality platforms are attitude, satisfaction, concentration, information quality, service quality, system quality, enjoyment, and time distortion. The findings could guide entrepreneurs and platform developers to develop a virtual reality platform suitable for ecommerce to enhance the consumer experience

Piezoelectric effects of single-crystal GaAs and multi-layered Al x Ga 1-x As/GaAs material measured by the Michelson interferometer

Abstract: Kheanumkeaw, P., Muensit, S. and Aiyarak, P. The inverse piezoelectric effect, in which the strains were electrically induced, in a single crystal of GaAs and in a multilayer structure of Al x Ga 1-x As/GaAs was measured using a simple optical system, i.e., Michelson interferometer. An ac driving voltage was applied to the sample to produce a change in the order of 10 -13 m in sample thickness. These changes were detected by the optical system to give the sample displacement as a function of applied driving voltage. The slope of the plot of this relationship led to the piezoelectric coefficients of (2.8±0.1)× × × × ×10 -12 and (3.9±0.1)× × × × ×10 -12 m/V for GaAs and Al x Ga 1-x As/GaAs, respectively. The first agreed well with reported values and the latter was the first report for Al x Ga 1-x As/GaAs. Owing to the equality for the inverse effect and the direct effect, in which an electric field can be mechanically induced, it is anticipated that in the absence of external electric field, the internal piezoelectric field can be induced in the multi-layered semiconductor. Piezoelectric effects of single-crystal GaAs and multi-layere

รูปแบบการจัดวางตัวทำงานเพียโซอิเล็กทริกและการเคลื่นที่ของคลื่นในมอเตอร์อัลตราโซนิคแบบเชิงเส้นโค้ง

Thailand Research Fund (TRF

Electrostrictive Energy Conversion of Polyurethane with Different Hard Segment Aggregations

This work reported the electrostriction of polyurethane (PU) with different aggregations of hard segments (HS) controlled by dissimilar solvents: N,N-dimethylformamide (DMF) and a mixture of dimethyl sulfoxide and acetone denoted as DMSOA. By using atomic force microscopy and differential scanning calorimetry, the PU/DMSOA was observed to have larger HS domains and smoother surface when compared to those of the PU/DMF. The increase of HS domain formation led to the increase of transition temperature, enthalpy of transition, and dielectric constant (0.1 Hz). For the applied electric field below 4 MV/m, the PU/DMSOA had higher electric-field-induced strain and it was opposite otherwise. Dielectric constant and Young’s modulus for all the samples were measured. It was found that PU/DMF had less dielectric constant, leading to its lower electrostrictive coefficient at low frequency. At higher frequencies the electrostrictive coefficient was independent of the solvent type. Consequently, their figure of merit and power harvesting density were similar. However, the energy conversion was well exhibited for low frequency range and low electric field. The PU/DMSOA should, therefore, be promoted because of high vaporizing temperature of the DMSOA, good electrostriction for low frequency, and high induced strain for low applied electric field

Effect of Piezoelectric Polarization on Phonon group velocity in Wurtzite Nitrides

We have investigated the effect of piezoelectric (PZ) polarization property on group velocity of phonons in binary as well as in ternary wurtzite nitrides. It is found that with the presence of PZ polarization property, the phonon group velocity is modified. The change in phonon group velocity due to PZ polarization effect directly depends on piezoelectric tensor value. Using different piezoelectric tensor values recommended by different workers in the literature, percent change in group velocities of phonons has been estimated. The Debye temperatures and frequencies of binary nitrides GaN, AlN and InN are also calculated using the modified group velocities. For ternary nitrides AlxGa(1-x)N, InxGa(1-x)N and InxAl(1-x)N, the phonon group velocities have been calculated as a functions of composition. A small positive bowing is observed in phonon group velocities of ternary alloys. Percent variations in phonon group velocities are also calculated for a straightforward comparison among ternary nitrides. The results are expected to show a change in phonon relaxation rates and thermal conductivity of III-nitrides when piezoelectric polarization property is taken into account.Comment: 05 figures; Journal of Material science, 201

Piezoelectric coefficients of gallium arsenide, gallium nitride and aluminium nitride

"1998"--T.p.Thesis (PhD)--Macquarie University, School of Mathematics, Physics, Computing and Electronics, 1999.Includes bibliographical references.Introduction -- A Michelson interferometer for measurement of piezoelectric coefficients -- The piezoelectric coefficient of gallium arsenide -- Extensional piezoelectric coefficients of gallium nitrides and aluminium nitride -- Shear piezoelectric coefficients of gallium nitride and aluminium nitride -- Electrostriction in gallium nitride, aluminium nitride and gallium arsenide -- Summary and prognosis.The present work represents the first use of the interferometric technique for determining the magnitude and sign of the piezoelectric coefficients of III-V compound semiconductors, in particular gallium arsenide (GaAs), gallium nitride (GaN), and aluminium nitride (AIN). The interferometer arrangement used in the present work was a Michelson interferometer, with the capability of achieving a resolution of 10⁻¹³ m. -- The samples used were of two types. The first were commercial wafers, with single crystal orientation. Both GaAs and GaN were obtained in this form. The second type of sample was polycrystalline thin films, grown in the semiconductor research laboratories at Macquarie University. GaN and AIN samples of this type were obtained. -- The d₁₄ coefficient of GaAs was measured by first measuring the d₃₃ value of a [111] oriented sample. This was then transformed to give the d₁₄ coefficient of the usual [001] oriented crystal. The value obtained for d₁₄ was (-2.7 ± 0.1) pmV⁻¹. This compares well with the most recent reported measurements of -2.69 pmV⁻¹. The significance of the measurement is that this represents the first time this coefficient has been measured using the inverse piezoelectric effect. -- For AIN and GaN samples, the present work also represents the first time their piezoelectric coefficients have been measured by interferometry. For GaN, this work presents the first reported measurements of the piezoelectric coefficients, and some of these results have recently been published by the (Muensit and Guy, 1998). The d₃₃ and d₃₁ coefficients for GaN were found to be (3.4 ± 0.1) pmV⁻¹ and (-1.7 ± 0.1) pmV⁻¹ respectively. Since these values were measured on a single crystal wafer and have been corrected for substrate clamping, the values should be a good measure of the true piezoelectric coefficients for bulk GaN. -- For AIN, the d₃₃ and d₃₁ coefficients were found to be (5.1 ± 0.2) pmV⁻¹, and (-2.6 ± 0.1) pmV⁻¹ respectively. Since these figures are measured on a polycrystalline sample it is quite probable that the values for bulk AIN would be somewhat higher.The piezoelectric measurements indicate that the positive c axis in the nitride films points away from the substrate. The piezoelectric measurements provide a simple means for identifying the positive c axis direction. -- The interferometric technique has also been used to measure the shear piezoelectric coefficient d₁₅ for AIN and GaN. This work represents the first application of this technique to measure this particular coefficient. The d₁₅ coefficients for AIN and GaN were found to be (-3.6 ± 0.1) pmV⁻¹ and (-3.1 ± 0.1) pmV⁻¹ respectively. The value for AIN agrees reasonably well with the only reported value available in the literature of -4.08 pmV⁻¹. The value of this coefficient for GaN has not been measured. -- Some initial investigations into the phenomenon of electrostriction in the compound semiconductors were also performed. It appears that these materials have both a piezoelectric response and a significant electrostrictive response. For the polycrystalline GaN and AIN, the values of the M₃₃ coefficients are of the order of 10⁻¹⁸ m²V⁻². The commercial single crystal GaN and GaAs wafers display an asymmetric response which cannot be explained.Mode of access: World Wide Web.Various pagings il

Experimental assessment of polyvinyledene fluoride coupled through standard approach for vibration-energy harvesting

This work presented the experimental analysis which focused on the realization of active volume within a crystallinephase of semi-crystalline PVDF samples on energy harvesting efficiency. The transformation of mechanical into electricalenergy was performed by PVDF connected directly in series to a standard interface circuit. This work investigated bothcommercial and synthesized PVDF. The maximum power of 2.6 mW was measured across the matching load of 1 M at 70 Hzexciting frequency from commercial PVDF of 28 mm thickness. A decrease in power was observed when the sample thicknessincreased. Generated power of prepared- and commercial-PVDF, however, were almost the same for the thickness of about50 mm with an active area of 4 cm2

Theory and measurements for 0-3 BaTiO3/PVDF composites

This work extended the range of material properties by fabricating the BaTiO3 /PVDF composite. In order to obtain the 0-3 composite without the interconnectivity of the ceramic powders, a low volume fractionof 0.3 of barium titanate (BaTiO3) was filled in a matrix of polyvinylidene fluoride (PVDF) and the mixture was homogeneously stirred. The composite was shaped into a sheet form by a tape casting method. Themicrostructure of the composite was observed using scanning electron microscopy (SEM) which revealed that the connectivity of the composite was mainly 0-3. Subsequently, theoretical models and equations wereapplied to the composite for comparisons with measurements. The density and heat capacity of the composites were experimentally obtained to be 3.21103 kg/m3 and 3021.7 J/kg oC, respectively. The compositewas corona poled before the test of dielectric response. Its 1 kHz-dielectric constant and dielectric loss at room temperature were 11.5 and 0.21, respectively. The good dielectric combined with the flexibility of thematerial implies that the composite is attractive for electronic applications where a light, environmentally friendly, ease to fabricate and low-cost device is required

การลดจำนวนตัวทำงานเพียโซอิเล็กทริกและพฤติกรรมของคลื่นเคลื่อนที่ในมอเตอร์อัลตราโซนิค : รายงานวิจัยฉบับสมบูรณ์โครงการ

Office of the Higher Education CommissionThailand Research Fun

Michelson interferometer for the piezoelectric coefficient measurements

The present work has described the Michelson interferometer which is capable of measuring the vibrational amplitudes in a sub-angstrom range. In the system, a He-Ne laser is used as a monochromatic source of light and a photodiode as a detector to convert an optical signal into an electronic one. Lock-in detections of the electronic signals are applied to relate the vibrational amplitudes to the wavelength of the laser beam. A feedback circuit is introduced in order to stabilize the sensitivity of the interferometric system. With this setup, a mechanical displacement referred to a change in thickness of a vibrating sample can be measured and the corresponding piezoelectric coefficient, i.e. the ratio of the change in sample thickness to the applied voltage, evaluated. In order to check the performance of the system, measurements on lithium niobate (LiNbO3) have been made and its piezoelectric coefficient d33 was confirmed with 2% accuracy. The piezoelectric coefficient d33 for lead zirconate titanate (PZT) ceramics was, therefore, determined by this interferometer and found to be 270 pm/V