scholarly journals Application of Piezoceramics in Relays

1976 ◽  
Vol 3 (1) ◽  
pp. 1-12 ◽  
Author(s):  
M. Guntersdorfer ◽  
P. Kleinschmidt ◽  
R. Veith
Keyword(s):  
Stress Distribution ◽  
The Other ◽  
Output Energy ◽  
Large Signal ◽  
Metal Part ◽  
Applied Electric Field Strength ◽  
Delayed Action ◽  
Bending Modes ◽  
Distribution Energy ◽  
Large Signal Behaviour

For the application of a piezoceramic as a d.c. electromechanical transducer to drive relay contacts the mechanical output energy is the most important feature. The energy has been calculated as a function of the applied electric field strength for longitudinal and transverse operation. For a typical ceramic material maximum values of 53 mWs/cm3(long.) and 21 mWs/cm3(trans.) are obtained, taking into account large signal behaviour. Conventional bending elements, which are used to achieve higher deflections at lower voltages, show transformation losses caused by inhomogeneous stress distribution, energy storage in the metal part and inactive bending modes. On the other hand by utilizing the effects of transverse clamping and stiffness compensation, the output energy can be increased by more than one decade as experimentally verified with some special types of highly efficient bending elements. A delayed action relay showing low temperature and shock sensitivity has been tested over more than 10 000 switching cycles.

scholarly journals The Effect of IP Constituent Position and Foot Complexity on Timing in Polish Learner's English Pronunciation

2010 ◽  
Vol 8 ◽  
pp. 149-162
Author(s):  
Andrzej Porzuczek
Keyword(s):  
Stress Distribution ◽  
The Other ◽  
Speech Timing ◽  
Other Hand ◽  
British School ◽  
English Pronunciation ◽  
Native Speech ◽  
As Stress

This paper focuses on the effect of prominence level and stress distribution on timing in read English speech of Polish learners. We have measured and analysed the length of IP units distinguished by the traditional British School prosodic description, i.e. preheads, heads and nuclei, as well as stress feet, further divided into stressed and unstressed syllables. A comparison of native and Polish learners' performance shows similar durations of stressed and pitch accented syllables. The unstressed syllables and syllable clusters, on the other hand, are significantly longer in non-native speech, and the discrepancies increase at lower phrasal prominence levels, especially in the preheads. Similar results for both groups have been obtained with respect to the number of consecutive unstressed syllables (foot complexity). The same test repeated after seven months of pronunciation training reveals a considerable tendency towards native speech timing, although the differences concerning low prominence levels remain significant.

scholarly journals Stress distribution in a rectangular plate having two opposing edges sheared in opposite directions

1923 ◽  
Vol 103 (723) ◽  
pp. 598-610 ◽  
Keyword(s):  
Shear Stress ◽  
Stress Distribution ◽  
Rectangular Plate ◽  
Royal Society ◽  
External Stress ◽  
The Other ◽  
Optical Methods ◽  
Centre Line ◽  
Distribution Of Stress

The type of deformation under investigation is indicated by fig. 1. A rectangular plate ABCD is deformed into the shape A'B'C'D'. The two opposing edges AB, CD are shifted horizontally without alteration of length into the position A'B', C'D', the other boundaries AD, BC being kept free from external stress. In a paper which appeared in the 'Proc. Royal Society', December 28, 1911, Prof. E. G. Coker investigated this same type of deformation using optical methods to determine the distribution of stress along the centre line OX. He found that if the plate was square the shear stress along OX was distributed in a munner which was approximately parabolic. As the ratio of AD to AB decreased the curve of distribution first of all became flat-topped, and for yet smaller ratios two distinct humps made their appearance.

scholarly journals A Comparative Three-Dimensional Finite Element Study of Two Space Regainers in the Mixed Dentition Stage

2020 ◽  
Vol 14 (01) ◽  
pp. 107-114
Author(s):  
Mohamed Ahmed Abdel Hakim ◽  
Nagwa Mohamed Ali Khatab ◽  
Kareem Maher Gaber Mohamed ◽  
Ahmad Abdel Hamid Elheeny
Keyword(s):  
Finite Element ◽  
Stress Distribution ◽  
Three Dimensional ◽  
The Other ◽  
Mixed Dentition ◽  
Von Mises Stress ◽  
Stress Concentrations ◽  
Permanent Molar ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

Abstract Objectives This study aims to compare the stress distribution and displacement that resulted from the use of a Gerber space regainer and sagittal distalizer using three-dimensional finite element analysis. Materials and Methods Three-dimensional simulated models of the appliances were developed using a software. The forces applied by the two appliances were 3N (tipping) and 15N (bodily), respectively. Displacement and von Mises stress on the compact and cancellous bone, periodontal ligament (PDL), crowns of the mandibular first, second permanent molars, and deciduous canines were calculated. Stress distribution and displacement values were measured via linear static analysis. Results Gerber space regainer showed greater displacement than that produced by the sagittal distalizer at the first permanent molar. However, such displacement was less at the other tested points when compared with that delivered by sagittal distalizer. The stresses created by Gerber appliance were higher in the crown and PDL of the deciduous canine than the crown of the first permanent molar crown. Conclusions Gerber appliance generates more distal force and less stress concentration on the crown of the mandibular first permanent molar than that created by the sagittal distalizer. On the other hand, stress concentrations produced by Gerber space regainer are found to be more on the crown and PDL of the deciduous canine. Therefore, it can be concluded that the use of Gerber appliance needs more anchorage.

The Simulation Analysis of MOSFET Channel Stress for Different Oxide/Nitride/Oxide (ONO) Spacer Thicknesses

2013 ◽  
Vol 699 ◽  
pp. 436-439
Author(s):  
J.Y. Chen ◽  
Z.H. Chen ◽  
K.C. Lin ◽  
M.J. Twu ◽  
Y.H. Hung ◽  
...  
Keyword(s):  
Stress Distribution ◽  
Simulation Analysis ◽  
The Other ◽  
Strained Si ◽  
Other Hand ◽  
Simulation Results ◽  
Spacer Thickness ◽  
Nitride Oxide ◽  
The Impact

It is demonstrated that the strained-Si can enhance the channel stress with the contact etching stop layer (CESL) stressor. In addition to CESL, this article also includes ONO spacer and investigates the impact of ONO spacer thickness on the channel stress. It is found that the channel stress increases when the nitride thickness of the ONO spacer increases. On the other hand, the stress distribution is simulated and analyzed for the devices with or without CESL stressor. Generally speaking, based on the simulation results, the channel stress of MOSFET devices increases when the nitride stressor of ONO spacer and/or CESL increases.

scholarly journals The biomechanical behavior of single crown implant-supported prosthesis with different types of connections and occlusal loads: Photoelastic and strain gauge analysis

2021 ◽  
Vol 10 (9) ◽  
pp. e26110918035
Author(s):  
Caroline de Freitas Jorge ◽  
Letícia Cerri Mazza ◽  
Marcio Campaner ◽  
Abbas Zahoui ◽  
Lorena Scaioni Silva ◽  
...  
Keyword(s):  
Stress Distribution ◽  
Strain Gauge ◽  
High Intensity ◽  
Axial Load ◽  
The Other ◽  
Biomechanical Behavior ◽  
Single Crown ◽  
Different Types ◽  
Connection System ◽  
Oblique Load

The aim of the study was to evaluate the biomechanical behavior, through photoelastic (PA) and strain gauge analysis (SA), of single crown implant-supported prosthesis with different implant connections (external hexagon (EH), Morse taper (MT), internal Morse hexagon (IMH), Morse taper hexagon (MTH), and frictional Morse taper (FMT)) and different occlusal loads (axial and oblique (45°)). The data were submitted to ANOVA and Tukey's test (α = 0,05). By photoelasticity, regarding axial load, EH produced more high-intensity fringes (2.784 kPa) than the other connections. For the oblique load, all connections generated the same high-intensity fringes (3.480 kPa), except by MT group, that produced the same amount as axial load (2.088 kPa). For the strain gauge analysis, for the axial load, EH showed the highest microstrains value (158,76) and lowets for MT (59,88). For all other groups, oblique load produced higher microstrains values than axial load. For the oblique load, MT showed the lowest microstrains value (88.79), followed by FMT (391,43), EH (468,47) and IMH (507,65). MTH presented the highest value (621,25) compared to all groups (P <0.05). When comparing both loads of the same connection system, only MT showed similar values (P <0.05). It was possible to conclude that the different connection systems tested directly influenced the stress distribution at both loads. The implants with internal connection present less stress distribution when submitted to axial load than the EH group. However, when the oblique load was applied, all connections presented higher values of stress distribution, except for the MT group.

Static Contact Characteristics Analysis of Wide Base Tire against Hot Asphalt Pavement

2014 ◽  
Vol 587-589 ◽  
pp. 1228-1232
Author(s):  
Ren Zhi Wu ◽  
Wei Du ◽  
Lin Qiang Shao ◽  
Zhi Nan Mi
Keyword(s):  
Finite Element ◽  
Stress Distribution ◽  
Contact Area ◽  
Asphalt Pavement ◽  
The Other ◽  
Inflation Pressure ◽  
Rigid Pavement ◽  
Static Contact ◽  
Characteristics Analysis ◽  
Contact Models

In order to analyze mechanism of pneumatic tire rollers compacting against hot asphalt pavement, taking the process of wide base tire of rollers compacting against hot asphalt pavement as research object, the wide base tire is loaded up with inflation pressure and axial force to study the contact characteristics. Two finite element contact models are established by ANSYS, one of which is for the contact of wide base tire against rigid pavement, and the other is for the contact of wide base tire against hot asphalt pavement. The static contact characteristics of wide base tire against hot asphalt pavement are achieved though FEA method, including whole deformation of tire, formation variation of contact patch, and stress distribution of contact area.

scholarly journals Quantum fidelity susceptibility in excited state quantum phase transitions: application to the bending spectra of nonrigid molecules

2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Jamil Khalouf-Rivera ◽  
Miguel Carvajal ◽  
Francisco Perez-Bernal
Keyword(s):  
Phase Transitions ◽  
Excited State ◽  
Molecular Species ◽  
Quantum Phase Transitions ◽  
Quantum Phase ◽  
The Other ◽  
Two Dimensional ◽  
Nonrigid Molecules ◽  
Bending Modes ◽  
Quantum Fidelity

We characterize excited state quantum phase transitions in the two dimensional limit of the vibron model with the quantum fidelity susceptibility, comparing the obtained results with the information provided by the participation ratio. As an application, we locate the eigenstate closest to the barrier to linearity and determine the linear or bent character of the different overtones for particular bending modes of six molecular species. We perform a fit and use the optimized eigenvalues and eigenstates in three cases and make use of recently published results for the other three cases.

Mode Identification for Rotating Rigid Shaft With Flexible Disks by Mode Splits

1999 ◽  
Author(s):  
Chong-Won Lee ◽  
Jong-Seok Ham
Keyword(s):  
Rotational Speed ◽  
Moment Of Inertia ◽  
The Other ◽  
Rotating Shaft ◽  
Coupled Modes ◽  
Nodal Diameter ◽  
Mode Identification ◽  
Other Hand ◽  
Bending Modes

Abstract This paper investigates the mode splits of the bending coupled modes of a rotating shaft with multiple flexible disks, in which the disks are rigidly attached to the rigid shaft supported by bearings. The bending coupled modes, in which shaft bending modes are coupled with one nodal diameter disk modes, are classified as the balanced and unbalanced modes. The mode splits of the balanced modes are the same as those of pure disk modes since the shaft does not experience any motion. On the other hand, the mode splits between pairs of the forward and backward unbalanced modes are found to be dependent upon the disk/shaft configuration and the shaft support stiffness, as well as the rotational speed and the ratio of polar to diametrical moment of inertia.

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