Fossil evidence is indispensable for studying the derivation, divergence, and dispersal of squirrels as they responded to global Cenozoic climatic paleoenvironmental change. Among these fossil records, earliest known definitive in Eurasia occur after Eocene/Oligocene Boundary are slightly younger than oldest records North America. Here, we report discovery two new extinct large squirrel species...

In this paper, fading mitigation by aperture averaging and receive diversity in Free-Space Optical (FSO) systems is experimentally investigated in a controlled atmospheric chamber. Some previous theoretical studies and the configuration of the experiment setup are described. Then, we introduce the turbulence measurement and performance evaluation for the FSO system briefly. The Q-factor is calc...

Results of a propagation study on a free space optical link at 850 nm on a path 853 meters long and on a parallel 58 GHz radio link obtained over a 3-year period of observation are presented. The cumulative distributions of attenuation due to all of the hydrometeors combined as well as due to individual hydrometeors were obtained for both paths. The availability performances of the FSO link, th...

Abstract – Free Space Optical (FSO) communication technology becomes a promising solution for the future optical broadband networks. This work is focused to carry out the investigation of the performance of Orthogonal Frequency Division Multiplexing (OFDM) FSO system using Optical Single Sideband (OSSB), Optical Double Sideband (ODSB) and Optical Vestigial Sideband (OVSB) modulation scheme by e...

PURPOSE We compared the emulsification tendency of silicone-phenylsilicone copolymer (DPC; 5%-phenylated, specific gravity 0.984) with that of silicone oil (SO; specific gravity 0.966) and fluorosilicone oil (FSO; specific gravity 1.256), all of which are used clinically as intraocular tamponades. METHODS We investigated the tendencies of emulsification in SO, FSO, and DPC. Each was placed in...

Free Space Optical (FSO) communication is a type of optical communication that relying on beams of light to transmit data over long distances wirelessly. With recent increase in popularity of the technology in commercial applications as well as military and scientific applications, it is important to study new models and algorithms to improve the performance of this technology. One of the most ...

We theoretically study the performance of multiple-input multiple-output (MIMO) free-space optical (FSO) systems using subcarrier quadrature modulation (SC-QAM) signaling. The system average symbolerror rate (ASER) is derived taking into account the atmospheric turbulence effects on the MIMO/FSO channel, which is modeled by log-normal and the gamma-gamma distributions for weak and moderate-to-s...