Experimental Evaluation of the Acoustic Impedance of Different Ground Types by Sound Propagation in Open-Air Environments

2014 ◽  
Vol 902 ◽  
pp. 185-191 ◽  
Author(s):  
Rafael A.C. Laranja ◽  
Vander M. Budel ◽  
Heraldo J. Amorim ◽  
Mario R. Sobczyk S.

This work presents an experimental characterization of three types of ground commonly found in urban centers regarding their absorption properties with respect to sound propagation: asphalt, grassland and soil. A brief theoretical background is presented, and the experimental procedure is discussed in detail. With basis on experimental results, it is concluded that grassland ground is mostly absorbent for all tested frequencies, whereas asphalt and soil are reflexive for low frequencies and absorbent for high ones.

2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Betsy Dayana Marcela Chaparro-Rico ◽  
Daniele Cafolla ◽  
Marco Ceccarelli ◽  
Eduardo Castillo-Castaneda

This paper presents an experimental characterization of NURSE, a device for arm motion guidance. The laboratory setup and testing modes are presented to explain the experimental procedure. Two exercises for the upper limb exercise are used to test the NURSE behaviour, and successful results are presented. Trajectories and linear accelerations are tested when the device performs the two exercises without and with load. In addition, torque and power consumption are considered to check the NURSE behaviour.


2002 ◽  
Vol 716 ◽  
Author(s):  
C. L. Gan ◽  
C. V. Thompson ◽  
K. L. Pey ◽  
W. K. Choi ◽  
F. Wei ◽  
...  

AbstractElectromigration experiments have been carried out on simple Cu dual-damascene interconnect tree structures consisting of straight via-to-via (or contact-to-contact) lines with an extra via in the middle of the line. As with Al-based interconnects, the reliability of a segment in this tree strongly depends on the stress conditions of the connected segment. Beyond this, there are important differences in the results obtained under similar test conditions for Al-based and Cu-based interconnect trees. These differences are thought to be associated with variations in the architectural schemes of the two metallizations. The absence of a conducting electromigrationresistant overlayer in Cu technology, and the possibility of liner rupture at stressed vias lead to significant differences in tree reliabilities in Cu compared to Al.


1982 ◽  
Vol 10 (1) ◽  
pp. 37-54 ◽  
Author(s):  
M. Kumar ◽  
C. W. Bert

Abstract Unidirectional cord-rubber specimens in the form of tensile coupons and sandwich beams were used. Using specimens with the cords oriented at 0°, 45°, and 90° to the loading direction and appropriate data reduction, we were able to obtain complete characterization for the in-plane stress-strain response of single-ply, unidirectional cord-rubber composites. All strains were measured by means of liquid mercury strain gages, for which the nonlinear strain response characteristic was obtained by calibration. Stress-strain data were obtained for the cases of both cord tension and cord compression. Materials investigated were aramid-rubber, polyester-rubber, and steel-rubber.


AIAA Journal ◽  
2002 ◽  
Vol 40 ◽  
pp. 16-25
Author(s):  
J. P. Wojno ◽  
T. J. Mueller ◽  
W. K. Blake

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