scholarly journals VCSEL Based Optoelectronic Oscillator (VBO) for 1.25 Gbit/s RZ Pulse Optical Data Generation

2018 ◽  
Author(s):  
Christian Daniel Munoz ◽  
Angelique Rissons ◽  
Fabien Destic ◽  
Juan Coronel Rico ◽  
Margarita Varon
Keyword(s):  
Optical Data ◽  
Data Generation ◽  
Optoelectronic Oscillator

scholarly journals A Tool for Pre-Operational Daily Mapping of Floods and Per-Manent Water Using Sentinel-1 Data

2021 ◽  
Vol 13 (7) ◽  
pp. 1342
Author(s):  
Luca Pulvirenti ◽  
Giuseppe Squicciarino ◽  
Elisabetta Fiori ◽  
Luca Ferraris ◽  
Silvia Puca
Keyword(s):  
Region Growing ◽  
Open Water ◽  
Optical Data ◽  
Management Service ◽  
Data Generation ◽  
End User ◽  
Mapping Algorithm ◽  
Output Layer ◽  
Water Mapping ◽  
Flood Maps

An automated tool for pre-operational mapping of floods and inland waters using Sentinel-1 data is presented. The acronym AUTOWADE (AUTOmatic Water Areas DEtector) is used to denote it. The tool provides the end user (Italian Department of Civil Protection) with a continuous, near real-time (NRT) monitoring of the extent of inland water surfaces (floodwater and permanent water). It implements the following operations: downloading of Sentinel-1 products; preprocessing of the products and storage of the resulting geocoded and calibrated data; generation of the intermediate products, such as the exclusion mask; application of a floodwater/permanent water mapping algorithm; generation of the output layer, i.e., a map of floodwater/permanent water; delivery of the output layer to the end user. The open floodwater/permanent water mapping algorithm implemented in AUTOWADE is based on a new approach, denoted as buffer-from-edge (BFE), which combines different techniques, such as clustering, edge filtering, automatic thresholding and region growing. AUTOWADE copes also with the typical presence of gaps in the flood maps caused by undetected flooded vegetation. An attempt to partially fill these gaps by analyzing vegetated areas adjacent to open water is performed by another algorithm implemented in the tool, based on the fuzzy logic. The BFE approach has been validated offline using maps produced by the Copernicus Emergency Management Service. Validation has given good results with a F1-score larger than 0.87 and a kappa coefficient larger than 0.80. The algorithm to detect flooded vegetation has been visually compared with optical data and aerial photos; its capability to fill some of the gaps present in flood maps has been confirmed.

1.28 Tbit/s single-polarisation serial OOK optical data generation and demultiplexing

2009 ◽  
Vol 45 (5) ◽  
pp. 280 ◽  
Author(s):  
H.C. Hansen Mulvad ◽  
L.K. Oxenløwe ◽  
M. Galili ◽  
A.T. Clausen ◽  
L. Grüner-Nielsen ◽  
...  
Keyword(s):  
Optical Data ◽  
Data Generation

Clock-Free RZ-BPSK Data Generation Using Self-Starting Optoelectronic Oscillator

2011 ◽  
Vol 29 (11) ◽  
pp. 1702-1707 ◽  
Author(s):  
Yu-Chieh Chi ◽  
Peng-Chun Peng ◽  
Gong-Ru Lin
Keyword(s):  
Data Generation ◽  
Optoelectronic Oscillator

The spindle stage: A powerful optical tool

1988 ◽  
Vol 46 ◽  
pp. 52-53
Author(s):  
Mickey E. Gunter ◽  
F. Donald Bloss
Keyword(s):  
Significant Error ◽  
Optical Data ◽  
Refractive Indices ◽  
Axis Of Rotation ◽  
Polarizing Microscope ◽  
Microscope Stage

A single, reasonably homogeneous, nonopaque 30-to-300 μm crystal, mounted on a spindle stage and studied by immersion methods under a polarizing microscope, yields optical data frequently sufficient to identify and characterize a substance unequivocally. The data obtainable include (1) the orientation of the crystal's principal vibration axes and (2) its principal refractive indices, to within 0.0002 if desired, for light vibrating along these principal vibration axes. Spindle stages tend to be simple and relatively inexpensive, some costing less than $50. They permit rotation of the crystal about a single axis which is parallel to the microscope stage. This spindle or S-axis is thus perpendicular to the M-axis, namely the microscope stage's axis of rotation.A spindle stage excels when studying anisotropic crystals. It orients uniaxial crystals within minutes and biaxial crystals almost as quickly so that their principal refractive indices - ɛ and ω (uniaxial); α, β and γ (biaxial) - can be determined without significant error from crystal misorientation.

Optical Data Links for L1 and Mars Missions

2005 ◽  
Author(s):  
M. Wittig ◽  
T. Dreischer ◽  
T. Weigl
Keyword(s):  
Optical Data ◽  
Data Links ◽  
Mars Missions
Sign in / Sign up

Export Citation Format

Share Document