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Showing 1 to 20 of 80 for “"Transmission Loss"”.
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Sound transmission loss characteristics of three layer composite wall constructions
Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Dept. of Mechanical Engineering.
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Sound Transmission Loss Between Spaces Connected by Multiple Paths: A Newmeasurement Technique
Made available in DSpace on 2014-12-10T19:06:53Z (GMT). No. of bitstreams: 1 7212372.pdf: 3257018 bytes, checksum: b726831fca5d5a6c2d72b9322a8936ab (MD5) Previous issue date: 1971
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Power Transmission Loss Due to Periodic Loading In Multi-Gigabit Data Signaling Interconnects
… influence the performance of PCB signal transmission. </p> <p>The nature of micro-scale periodic structures of PCB materials is not well understood, especially at millimeter wavelength frequencies required to transmit high-speed digital signals. Researchers have observed unexplained …
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Environmental analysis and prediction of transmission loss in the region of the New England Shelfbreak
… to bottom sediments is the major contributor of transmission loss in the ocean. In shallow water, available propagation paths most often include bottom interaction. Perturbations in the ocean sound speed field can cause changes in the angle of incidence of sound rays with the bottom, which can …
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Environmental analysis and prediction of transmission loss in the region of the New England Shelfbreak
… to bottom sediments is the major contributor of transmission loss in the ocean. In shallow water, available propagation paths most often include bottom interaction. Perturbations in the ocean sound speed field can cause changes in the angle of incidence of sound rays with the bottom, which can …
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An Investigation on Acoustic Metamaterial Physics to Inspire the Design of Novel Aircraft Engine Liners
… and their ability to achieve superior transmission loss characteristics not found in traditional honeycomb liners. The acoustic metamaterials investigated are an array of Helmholtz resonators with and without coupled cavities periodically-spaced along a duct wall. Analytical, numerical, …
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Some Effects of Loss Formula Variation on Power System Production Costs.
The use of a transmission loss formula in economic dispatch of generation is the most common approach in modern power system operation. A great deal of literature has been devoted to the problem of calculating accurate loss formulae. Several methods employ quite lengthy attempts to establish the …
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Modelling the sound insulation of corrugated roof structures : an extended transfer matrix approach
… The same principles were applied in deriving the transmission loss through periodically stiffened plates, as a proxy for corrugated panels. At the same time, corrugated plates were modelled as equivalent orthotropic panels, a process which is compatible with the TMM without particular …
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Structure-acoustic analysis; finite element modelling and reduction methods
… the interior noise in a vehicle or the sound transmission loss in a wall between two dwellings. The geometrical properties of the studied system and the frequency limit of interest for the analysis determine the size of the system of equations to be solved. This size often becomes very large …
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Analysis of dynamic acoustic source positioning : an autonomous swarm approach
… positioning algorithm was developed to reduce transmission loss from the source agent to a given target as it changes position over time. Several operating profiles, that govern the behavior of interacting source agents through modification of the objective function, were also developed. …
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Improved draw process in optical fiber fabrication
… To get fibers with higher strength and lower transmission loss, the parameters of the draw process must be optimized and the geometric uniformity of the fiber must be maintained with high precision. To increase the geometric uniformity of the fiber the online fiber diameter measuring accuracy …
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Control of Sound Transmission with Active-Passive Tiles
Nowadays, numerous applications of active sound transmission control require lightweight partitions with high transmission loss over a broad frequency range and simple control strategies. In this work an active-passive sound transmission control approach is investigated that potentially addresses …
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The acoustic modelling of dissipative elements in automotive exhausts
… is assessed in the light of experimental sound transmission loss data measured for five different dissipative silencers. Mean flow in the central channel is a feature of each model, in addition to the use of the new semiempirical models for the perforated tube and the absorbent. A simple …
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Fabrication and Evaluation of Specialty Nonwoven Materials
… thermogravimetric analysis, sound absorption and transmission loss, scanning electronic microscopy and surface properties. Carbonization of cotton nonwoven was carried out in a high temperature oven with nitrogen between 300 °C and 500 °C. The physical activation was undertaken using CO2. The N2 …
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Effects of atmospheric profiles on local infrasound propagation
… in wavenumber is used for calculating transmission loss. A large number of simulations were performed to investigate the effect that meteorological profiles in different layers of the atmosphere have on surface transmission loss and to assess the impact of varying these profiles. Wind …
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Low Frequency Noise Reduction Using Novel Poro-Elastic Acoustic Metamaterials
… to improve low frequency sound absorption and transmission loss using acoustic metamaterials. The acoustic metamaterials investigated consist of poro-elastic acoustic heterogeneous (HG) metamaterials and microperforated (MPP) acoustic metamaterials. HG metamaterials consist of poro-elastic …
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Active control methods for improving the insertion loss of acoustical enclosures
… noise control is the implementation of passive transmission loss enclosures. An acoustical enclosure surrounds a noise source for the purpose of interrupting the noise transmission path. The effectiveness of these enclosures is, however, limited by various drawbacks. These drawbacks include …
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