Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 15 of 15 for “"material damping"”.
-
Drum Sound Synthesis by Computer Simulation of the Wave Equation
… takes into account the stiffness of the drumhead material, damping due to energy dissipation into the air and rim, mass loading of the air, and changing tension caused by stretching of the drumhead.
-
ΑΝΑΓΝΩΡΙΣΗ ΙΔΙΟΜΟΡΦΩΝ ΤΑΛΑΝΤΟΥΜΕΝΩΝ ΠΛΑΚΩΝ ΑΠΟ ΘΕΡΜΟΚΡΑΣΙΑΚΕΣ ΜΕΤΡΗΣΕΙΣ
MATERIAL DAMPING AND ASSOCIATED ENERGY DISSIPATION IN A VIBRATING PLATE RESULTSIN A TEMPERATURE INCREASE. GIVEN THE HARMONIC MOTION OF THE BOUNDARY, THE STEADY VIBRATION OF PLATES AND THE DAMPING HEAT, GENERATED IS COMPUTED. THEN THE HEAT CONDUCTION EQUATION YIELDS THE TEMPERATURE DISTRIBUTION. THE …
-
Development of the Spectral-Analysis-of-Body-Waves (SABW) method for downhole seismic testing with boreholes or penetrometers
… wave characteristics such as wave dispersion and material damping. An alternate approach is to use frequency-domain analysis methods which are well suited for evaluating time changes between all types of waveforms measured at spatially different points. In addition, frequency-domain methods can be …
-
Resposta dinâmica não-linear da interação solo-estrutura no domínio da frequência
… of a complex values linear equations. The material damping is considered through the complex shear moduli. ln this way, the system steady-state response for an harmonic excitations is obtained. The nonlinear soil behavior is considered by performing a iterative linear analysis (Equivalent …
-
Effects of oversized particles on the dynamic properties of sand specimens evaluated by resonant column testing
… by gravel particles on the shear modulus (G) and material damping ratio (D) of a uniform sand were evaluated in the linear (γ ≤ 0.001%) and nonlinear (γ > 0.001%) ranges of shear strain with combined resonant column and torsional shear (RCTS) equipment. The sand used in this investigation is a …
-
OPTIMIZATION OF A PIEZOELECTRIC ACOUSTICAL COMPRESSOR
… includes the effects of viscous and thermal damping of the fluid at the boundary of the cavity, and material damping in the piezoelectric actuator. Two types of piezoelectric actuators are considered, a stacked layer actuator, and a bending bimorph actuator. The resulting finite element …
-
ΕΛΕΓΧΟΜΕΝΗ ΔΙΑΔΟΣΗ ΡΩΓΜΩΝ ΛΟΓΩ ΚΟΠΩΣΗΣ ΣΕ ΣΥΝΘΗΚΕΣ ΣΥΝΤΟΝΙΣΜΟΥ
… THAN A THRESHOLD LEVEL, CHARACTERISTIC OF THE MATERIAL CONSIDERED. THIS PHENOMENON CAN BE INTERPRETED AS DYNAMIC CRACK ARREST. FOR STRUCTURAL MEMBERS AND IF THE MATERIAL DAMPING DOMINATES, THE LOSS COEFFICIENT IS PROVED TO BE THE MAIN FACTOR DETERMINING DECISIVELY THE CRACK PROPAGATION RATE AT …
-
Acoustics and manufacture of Caribbean steelpans
… are situated in the production, vibration and material aspect of the steelpan. A novel sheet forming technology termed Incremental Sheet Forming (ISF) is applied to the production of miniature steelpan dishes. The thickness distribution in the wall of the ISF dishes is compared to the wall …
-
Influence of some particle characteristics on the small strain response of granular materials
… representing the small strain response of geomaterials are the very small strain shear modulus, Gmax, shear modulus degradation G/Gmax, and damping ratio. These are also important parameters in the design of foundations where only small deformation takes place. A review of the literature …
-
Investigations on Void Formation in Composite Molding Processes and Structural Damping in Fiber-Reinforced Composites with Nanoscale Reinforcements
… and lighter weight alternative to traditional materials used in engineering components such as wind turbine blades and rotorcraft structures. Composites for these applications are often fabricated using liquid molding techniques, such as injection molding or resin transfer molding. One …
-
Comparison and Analysis of the Strength, Stiffness, and Damping Characteristics of Concrete with Rubber, Latex, and Carbonate Additives
… to investigate methods for increasing the damping capacity of concrete. A variety of additives, both particle and latex based, were added to standard concrete mixtures by replacing up to 20% of the fine aggregate to measure their effects on strength, stiffness, damping, and air content. The …
-
Modeling and control of flexible structures
… on a string and on a beam, both with slight material damping. Direct feedback proves superior for the string, as more modes must be controlled than can be handled by modal control with a limited number of actuators, but inferior for the beam, as effort is wasted suppressing motion in higher …
-
IMPROVEMENT OF DYNAMIC PROPERTIES AND SEISMIC RESPONSE OF CLAY USING FIBER REINFORCEMENT
… Method to obtain both the shear modulus and the material damping for a clay and the fiber-clay composite to determine the effect of fiber inclusion on the dynamic properties of clayey soil. The research showed that the inclusion of fiber at optimum fiber content as a ground improvement technique …
-
Analysis of the sensing region of a PZT actuator-sensor
… health monitoring at the Center for Intelligent Material Systems and Structures (CIMSS) [1-3]. This new technique uses piezoceramic (PZT) patches as actuator-sensors to provide a low-power driven constant voltage dynamic excitation, and to record the modulated current flow through the structure. …
-
Material and Damping Characterization of Discretized Adhesive Tapes in Cantilever Beams undergoing Free and Forced Vibration
… investigating the effectiveness of discretized damping tapes applied to a cantilever beam subjected to free and forced vibrations. The work is divided into three main sections. First, we performed material characterization of the viscoelastic (VE) pressure sensitive adhesive layer of the damping …