Results 251 to 260 of about 166,209 (277)

The underwater visual environment

1990
What does the term ‘vision’ mean when applied to non-human animals, and how is the structure and function of a visual system adaptive for the animal that possesses it? These fundamental questions drive the visual ecologist and differentiate her or him from the photoecologist, who is interested in general sensitivity problems.
Ellis R. Loew, William N. McFarland
openaire   +1 more source

Photogrammetric modeling of underwater environments

ISPRS Journal of Photogrammetry and Remote Sensing, 2010
Underwater photogrammetry provides an efficient nondestructive means for measurement in environments with limited accessibility. With the growing use of consumer cameras, its application is becoming easier, thus benefiting a wide variety of disciplines. However, utilizing cameras for underwater photogrammetry poses some nontrivial modeling problems due
Gili Telem, Sagi Filin
openaire   +1 more source

Movement Time in an Underwater Environment

Journal of Motor Behavior, 1973
The effect of an underwater environment on the human motor capacity, as measured by Fitts' Law, was determined. Five Ss performed a reciprocal tapping task both on land and underwater. The results showed that movement time (MT) was significantly slower (p < 01) underwater than on land.
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Bioinspired visual guidance in turbid underwater environment

2017 IEEE SENSORS, 2017
In this paper, an obstacle avoidance strategy using monocular gray-scale robotic vision for turbid water environments is presented. Biologically inspired by the unique vision system of the cubozoan, or box jellyfish, the proposed obstacle avoidance techniques were designed to be as computationally inexpensive as possible for implementation in a compact
Zhuoyuan Song, Schwartz, Eric, Mohseni, Kamran   +2 more
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A simulation environment for Autonomous Underwater Vehicles

OCEANS 2009-EUROPE, 2009
This paper gives an overview of the AUVFramework, a simulation environment for the evaluation of concepts regarding AUVs. An infrastructure of functionalities (maps, interface to kinematics, communication between multiple AUVs) supports the development of autonomous control.
Kobialka, Hans-Ulrich, Wunderlich, T.
openaire   +1 more source

Omnet++ Based Simulation for Underwater Environment

2008 IEEE/IFIP International Conference on Embedded and Ubiquitous Computing, 2008
This paper describes about underwater data transmission simulator. Analysis procedures for various underwater environments and other factors were analyzed. A new simulator based on the analysis results was implemented and performance evaluations were conducted using the developed simulator considering various ack techniques into account.
Soo Young Shin, Soo Hyun Park
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Non-parametric detection in underwater environments

International Conference on Acoustics, Speech, and Signal Processing, 2003
Motivated by the recurring use of the generalized Gaussian family to model different underwater noise sources and the asymptotic performance levels of some commonly used detectors for this family, the authors examined the performance of these detectors for several different underwater noise sources.
P.A. Nielsen, J.B. Thomas
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The Arctic underwater acoustic environment.

The Journal of the Acoustical Society of America, 2010
This talk gives an overview of the underwater acoustic environment in the Arctic. Sources of sound will be reviewed, including natural ambient noise (physical + biological) and man-made noise. Sound propagation characteristics will be discussed and examples from field studies will be presented.
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Underwater acoustic propagation in Arctic environments

The Journal of the Acoustical Society of America, 2011
Developments in underwater acoustic modeling for the Arctic have been limited due to the complicated nature of the polar extreme. In Arctic regions, the sound speed minimum occurs at or near the ice-covered surface. The upward refracting sound speed profile causes any long-range propagation to repeatedly interact with the ice cover. This paper presents
Christie A. O'Hara, Jon M. Collis
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Robust Visual Odometry in Underwater Environment

2018 OCEANS - MTS/IEEE Kobe Techno-Oceans (OTO), 2018
The accurate estimation of pose and velocity of an autonomous underwater vehicle (AUV) is critical to ensure the repeatability and validity of scientific data that is captured using sensors onboard the AUV. A low-cost and effective way is by using stereo camera sensors to perform visual odometry (VO).
Jun Zhang, Viorela Ila, Laurent Kneip
openaire   +1 more source