keyword
MENU ▼
Read by QxMD icon Read
search

vibration plate

keyword
https://www.readbyqxmd.com/read/28531144/impact-damage-localisation-with-piezoelectric-sensors-under-operational-and-environmental-conditions
#1
Mohammad Saleh Salmanpour, Zahra Sharif Khodaei, M H Ferri Aliabadi
Guided-wave structural health monitoring (SHM) systems with piezoelectric sensors are investigated for localisation of barely visible impact damage in CFRP plates under vibration and different thermal conditions. A single baseline set is used in a delay-and-sum algorithm with temperature correction for damage localisation in a large temperature range. Damage localisation is also demonstrated under transient thermal conditions, with signals recorded while the temperature is rapidly decreased. Damage severity due to successive impact events is studied under constant temperature...
May 22, 2017: Sensors
https://www.readbyqxmd.com/read/28515484/the-complex-tibial-organ-of-the-new-zealand-ground-weta-sensory-adaptations-for-vibrational-signal-detection
#2
Johannes Strauß, Kathryn Lomas, Laurence H Field
In orthopteran insects, a complex tibial organ has evolved to detect substrate vibrations and/or airborne sound. Species of New Zealand weta (Anostostomatidae) with tympanal ears on the foreleg tibia use this organ to communicate by sound, while in atympanate species (which communicate by substrate drumming) the organ is unstudied. We investigated the complex tibial organ of the atympanate ground weta, Hemiandrus pallitarsis, for vibration detection adaptations. This system contains four sensory components (subgenual organ, intermediate organ, crista acustica homolog, accessory organ) in all legs, together with up to 90 scolopidial sensilla...
May 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28509870/sound-power-estimation-for-beam-and-plate-structures-using-polyvinylidene-fluoride-films-as-sensors
#3
Qibo Mao, Haibing Zhong
The theory for calculation and/or measurement of sound power based on the classical velocity-based radiation mode (V-mode) approach is well established for planar structures. However, the current V-mode theory is limited in scope in that it can only be applied to conventional motion sensors (i.e., accelerometers). In this study, in order to estimate the sound power of vibrating beam and plate structure by using polyvinylidene fluoride (PVDF) films as sensors, a PVDF-based radiation mode (C-mode) approach concept is introduced to determine the sound power radiation from the output signals of PVDF films of the vibrating structure...
May 16, 2017: Sensors
https://www.readbyqxmd.com/read/28484335/coupling-strength-assumption-in-statistical-energy-analysis
#4
T Lafont, N Totaro, A Le Bot
This paper is a discussion of the hypothesis of weak coupling in statistical energy analysis (SEA). The examples of coupled oscillators and statistical ensembles of coupled plates excited by broadband random forces are discussed. In each case, a reference calculation is compared with the SEA calculation. First, it is shown that the main SEA relation, the coupling power proportionality, is always valid for two oscillators irrespective of the coupling strength. But the case of three subsystems, consisting of oscillators or ensembles of plates, indicates that the coupling power proportionality fails when the coupling is strong...
April 2017: Proceedings. Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/28481501/high-throughput-investigation-of-a-lead-free-aln-based-piezoelectric-material-mg-hf-xal1-xn
#5
Hung H Nguyen, Hiroyuki Oguchi, Le Van Minh, Hiroki Kuwano
We conducted a high-throughput investigation of the fundamental properties of (Mg,Hf)xAl1-xN thin films (0 < x < 0.24) aiming for developing high-performance AlN-based piezoelectric materials. For the high-throughput investigation, we prepared composition-gradient (Mg,Hf)xAl1-xN films grown on a Si(100) substrate at 600 °C by cosputtering AlN and MgHf targets. To measure the properties of the various compositions at different positions within a single sample, we used characterization techniques with spatial resolution...
May 16, 2017: ACS Combinatorial Science
https://www.readbyqxmd.com/read/28469755/can-different-complex-training-improve-the-individual-phenomenon-of-post-activation-potentiation
#6
Zong-Rong Chen, Shin-Liang Lo, Min-Hsien Wang, Ching-Fang Yu, Hsien-Te Peng
The aims of the present study were (a) to determine whether the two types of complex training and vibration complex training would improve the individual phenomenon of post-activation potentiation (PAP) for every athlete in a team setting; and (b) to compare the acute effect of resistance and plyometric exercise, whole body vibration, complex training and vibration complex training on vertical jump performance. The participants were ten male division I college volleyball and basketball players. They were asked to perform three vertical jumps as a pre-test and were then randomly assigned to one of five PAP protocols, resistance exercise using half squat exercise, plyometric exercise using drop jumps with individualized drop height, whole body vibration using squats on a vibration plate, complex training combining resistance exercise with plyometric exercise, vibration complex training combining whole body vibration with plyometric exercise...
February 2017: Journal of Human Kinetics
https://www.readbyqxmd.com/read/28436860/effect-on-high-intensity-fields-of-a-tough-hydrophone-with-hydrothermal-pzt-thick-film-vibrator-and-titanium-front-layer
#7
Nagaya Okada, Shinichi Takeuchi
A novel tough hydrophone was fabricated by depositing hydrothermally synthesized lead zirconate titanate polycrystalline film on the back-side surface of a titanium plate. Our developed tough hydrophone resisted damage in a high-pressure field (15 MPa) at a focal point of a sinusoidal continuous wave driven by a concave high-intensity focused ultrasound (HIFU) transducer with up to 50 W of power input to the sound source. The hydrophone was suitable for the HIFU field, even though the hydrophone has a flat-shape tip of 3...
April 24, 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/28425516/mechanical-and-vibrational-characterization-of-amyloid-like-het-s-nanosheets-based-on-the-skewed-plate-theory
#8
Hyun Joon Chang, Myeongsang Lee, Jae In Kim, Gwonchan Yoon, Sungsoo Na
Pathological amyloidogenic prion proteins have a toxic effect on functional cells in the human cerebrum because of poor degradability and the tendency to accumulate in an uncontrolled manner under physiological conditions. HET-s, a fungal prion protein, is known to undergo conformational variations from fibrillar to nanosheet structures during a change from low to high pH conditions. It has been said that this conformational change can lead to self-propagation by nucleating on the lateral surface of singlet fibrils...
April 20, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28372094/vibration-damping-using-a-spiral-acoustic-black-hole
#9
Jae Yeon Lee, Wonju Jeon
This study starts with a simple question: can the vibration of plates or beams be efficiently reduced using a lightweight structure that occupies a small space? As an efficient technique to damp vibration, the concept of an acoustic black hole (ABH) is adopted with a simple modification of the geometry. The original shape of an ABH is a straight wedge-type profile with power-law thickness, with the reduction of vibration in beams or plates increasing as the length of the ABH increases. However, in real-world applications, there exists an upper bound of the length of an ABH due to space limitations...
March 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28367593/analytical-and-numerical-stability-analysis-of-soret-driven-convection-in-a-horizontal-porous-layer-the-effect-of-vertical-vibrations
#10
Soumaya Ouadhani, Ali Abdennadher, Abdelkader Mojtabi
The authors studied the effect of vertical high-frequency and small-amplitude vibrations on the separation of a binary mixture saturating a porous cavity. The horizontal bottom plate was submitted to constant uniform heat flux and the top one was maintained at constant temperature while no mass flux was imposed. The influence of vertical vibrations on the onset of convection and on the stability of the unicellular flow was investigated for positive separation ratio [Formula: see text]. The case of high-frequency and small-amplitude vibrations was considered so that a formulation using time averaged equations could be used...
April 2017: European Physical Journal. E, Soft Matter
https://www.readbyqxmd.com/read/28336861/modified-continuum-mechanics-modeling-on-size-dependent-properties-of-piezoelectric-nanomaterials-a-review
#11
REVIEW
Zhi Yan, Liying Jiang
Piezoelectric nanomaterials (PNs) are attractive for applications including sensing, actuating, energy harvesting, among others in nano-electro-mechanical-systems (NEMS) because of their excellent electromechanical coupling, mechanical and physical properties. However, the properties of PNs do not coincide with their bulk counterparts and depend on the particular size. A large amount of efforts have been devoted to studying the size-dependent properties of PNs by using experimental characterization, atomistic simulation and continuum mechanics modeling with the consideration of the scale features of the nanomaterials...
January 26, 2017: Nanomaterials
https://www.readbyqxmd.com/read/28253676/time-reversal-focusing-of-elastic-waves-in-plates-for-an-educational-demonstration
#12
Christopher Heaton, Brian E Anderson, Sarah M Young
The purpose of this research is to develop a visual demonstration of time reversal focusing of vibrations in a thin plate. Various plate materials are tested to provide optimal conditions for time reversal focusing. Specifically, the reverberation time in each plate and the vibration coupling efficiency from a shaker to the plate are quantified to illustrate why a given plate provides the best spatially confined focus as well as the highest focal amplitude possible. A single vibration speaker and a scanning laser Doppler vibrometer (SLDV) are used to provide the time reversal focusing...
February 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28252394/development-of-an-acoustic-levitation-linear-transportation-system-based-on-a-ring-type-structure
#13
Gilles P L Thomas, Marco A B Andrade, Julio Cezar Adamowski, Emilio Carlos Nelli Silva
A linear acoustic levitation transportation system based on a ring-type vibrator is presented. The system is composed by two 21-kHz Langevin transducers connected to a ring-shaped structure formed by two semicircular sections and two flat plates. In this system, a flexural standing wave is generated along the ring structure, producing an acoustic standing wave between the vibrating ring and a plane reflector located at a distance of approximately a half wavelength from the ring. The acoustic standing wave in air has a series of pressure nodes, where small particles can be levitated and transported...
May 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/28249528/low-vibration-laboratory-with-a-single-stage-vibration-isolation-for-microscopy-applications
#14
Bert Voigtländer, Peter Coenen, Vasily Cherepanov, Peter Borgens, Thomas Duden, F Stefan Tautz
The construction and the vibrational performance of a low vibration laboratory for microscopy applications comprising a 100 ton floating foundation supported by passive pneumatic isolators (air springs), which rest themselves on a 200 ton solid base plate, are discussed. The optimization of the air spring system leads to a vibration level on the floating floor below that induced by an acceleration of 10 ng for most frequencies. Additional acoustic and electromagnetic isolation is accomplished by a room-in-room concept...
February 2017: Review of Scientific Instruments
https://www.readbyqxmd.com/read/28248509/young-s-equation-for-a-two-liquid-system-on-the-nanometer-scale
#15
J-C Fernandez-Toledano, T D Blake, J De Coninck
We use large-scale molecular dynamics simulations to study the Lennard-Jones forces acting at the various interfaces of a liquid bridge (liquid 1) between two realistic solid plates on the scale of few nanometers when the two free surfaces are in contact with a second immiscible liquid (liquid 2) with an interfacial tension of γ12. Each plate comprises a regular square planar lattice of atoms arranged in three atomic layers. To maintain rigidity while allowing momentum exchange with the liquid, solid atoms are allowed to vibrate thermally around their initial positions by a strong harmonic potential...
March 8, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28237824/damage-detection-of-fatigue-cracks-under-nonlinear-boundary-condition-using-subharmonic-resonance
#16
Mengyang Zhang, Li Xiao, Wenzhong Qu, Ye Lu
In recent years, the nonlinear ultrasonic technique has been widely utilized for detecting fatigue crack, one of the most common forms of damage. However, one of limitations associated with this technique is that nonlinearities can be produced not only by damage but also by various intrinsic effects such as boundary conditions. The objective of this paper is to demonstrate the application of a nonlinear ultrasonic subharmonic method for detecting fatigue cracks with nonlinear boundary conditions. The fatigue crack was qualitatively modeled as two elastic, frictionless half spaces that enter into contact during vibration and where the contact obeys the basic Hertz contact law...
May 2017: Ultrasonics
https://www.readbyqxmd.com/read/28222002/friction-reduction-through-ultrasonic-vibration-part-1-modelling-intermittent-contact
#17
Eric Vezzoli, Zlatko Virdih, Vincenzo Giamundo, Betty Lemaire-Semail, Frederic Giraud, Tomaz Rodic, Djordje Peric, Michael Adams
Ultrasonic vibration is employed to modify the friction of a finger pad in way that induces haptic sensations. A combination of intermittent contact and squeeze film levitation has been previously proposed as the most probable mechanism. In this paper, in order to understand the underlying principles that govern friction modulation by intermittent contact, numerical models based on finite element (FE) analysis and also a spring-Coulombic slider are developed. The physical input parameters for the FE model are optimised by measuring the contact phase shift between a finger pad and a vibrating plate...
February 17, 2017: IEEE Transactions on Haptics
https://www.readbyqxmd.com/read/28222001/friction-reduction-through-ultrasonic-vibration-part-2-experimental-evaluation-of-intermittent-contact-and-squeeze-film-levitation
#18
Thomas Sednaoui, Eric Vezzoli, Brygida Maria Dzidek, Betty Lemaire-Semail, Cedrick Chappaz, Michael Adams
In part 1 of the current study of haptic displays, a finite element (FE) model of a finger exploring a plate vibrating out-of-plane at ultrasonic frequencies was developed as well as a spring-frictional slider model. It was concluded that the reduction in friction induced by the vibrations could be ascribed to ratchet mechanism as a result of intermittent contact. The relative reduction in friction calculated using the FE model could be superimposed onto an exponential function of a dimensionless group defined from relevant parameters...
February 17, 2017: IEEE Transactions on Haptics
https://www.readbyqxmd.com/read/28130556/the-new-vestibular-stimuli-sound-and-vibration-anatomical-physiological-and-clinical-evidence
#19
REVIEW
Ian S Curthoys
The classical view of the otoliths-as flat plates of fairly uniform receptors activated by linear acceleration dragging on otoconia and so deflecting the receptor hair bundles-has been replaced by new anatomical and physiological evidence which shows that the maculae are much more complex. There is anatomical spatial differentiation across the macula in terms of receptor types, hair bundle heights, stiffness and attachment to the overlying otolithic membrane. This anatomical spatial differentiation corresponds to the neural spatial differentiation of response dynamics from the receptors and afferents from different regions of the otolithic maculae...
April 2017: Experimental Brain Research. Experimentelle Hirnforschung. Expérimentation Cérébrale
https://www.readbyqxmd.com/read/28125270/response-to-tendon-vibration-questions-the-underlying-rationale-of-proprioceptive-training
#20
Anat Vilnai Lubetzky, Sarah Westcott McCoy, Robert Price, Deborah Kartin
CONTEXT: Proprioceptive training on compliant surfaces is used to rehabilitate and prevent ankle sprains. The ability to improve proprioceptive function via such training has been questioned. Achilles tendon vibration is used in motor-control research as a form of proprioceptive stimulus. Using measures of postural steadiness with nonlinear measures to elucidate control mechanisms, tendon vibration can be applied to investigate the underlying rationale of proprioceptive training. OBJECTIVE: To test whether the effect of vibration on young adults' postural control depended on the support surface...
February 2017: Journal of Athletic Training
keyword
keyword
93795
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"