7,453 research outputs found
Empirical Modeling of Ducting Effects on a Mobile Microwave Link Over a Sea Surface
In this paper, signal enhancement due to the ducts over a sea surface is experimentally investigated and modeled. The investigation is carried out through the study of air-to-ground mobile microwave links over a tropical ocean with low airborne altitudes (0.37 - 1.83 km) at C band (5.7 GHz). The distance-dependence of the ducting induced enhancement (with reference to the free-space propagation) is linearly modeled, and the physical variations of the ducts are found to be Gaussian distributed. Empirical ducting coefficients and parameters for the Gaussian function are estimated and provided for the prediction of the distance-dependent signal enhancement due to the ducts in similar scenarios
Correlating Satellite Cloud Cover with Sky Cameras
The role of clouds is manifold in understanding the various events in the
atmosphere, and also in studying the radiative balance of the earth. The
conventional manner of such cloud analysis is performed mainly via satellite
images. However, because of its low temporal- and spatial- resolutions,
ground-based sky cameras are now getting popular. In this paper, we study the
relation between the cloud cover obtained from MODIS images, with the coverage
obtained from ground-based sky cameras. This will help us to better understand
cloud formation in the atmosphere - both from satellite images and ground-based
observations.Comment: Published in Proc. Progress In Electromagnetics Research Symposium
(PIERS), 201
EFFECTS OF WHOLE BODY VIBRATION TRAINING ON KNEE EXTENSOR MUSCLE STRENGTH AND RATE OF FORCE DEVELOPMENT
This study compared the effects of 8-week whole-body vibration (WBV) training programs on knee extensor muscle strength and rate of force development. Twenty physically active male subjects were randomly assigned to a whole-body vibration training group (WBV; n =10) or a sham training group (SHAM; n = 10). Maximal voluntary isometric joint moment, rate of force development (RFD) and contractile impulse of the knee extensors were assessed before and after the training period. There were significant differences between WBV and sham groups on improvement percentage of maximum joint moment, RFD and
contractile impulse in knee extensor. We concluded that not only knee extensor muscle strength could be enhanced but also muscle contractile abilty could be faster after a 8-week WBV training program
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