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  • motion
  • Compared to the implementation with one scale our multi-scale approach generates faster dense flow fields and reduces wrong motion estimations. (springer.com)
  • For many animals, including humans, the optic flow generated on the eyes during locomotion is an important source of information about self-motion and the structure of the environment. (jneurosci.org)
  • When flying through narrow spaces, insects control their position by balancing the magnitude of apparent image motion (optic flow) experienced in each eye and their speed by holding this value about a desired set-point. (lu.se)
  • article{de4300f1-6416-4925-99a4-0c5db7d5cc85, abstract = {When flying through narrow spaces, insects control their position by balancing the magnitude of apparent image motion (optic flow) experienced in each eye and their speed by holding this value about a desired set-point. (lu.se)
  • Electroencephalogram (EEG) was used in preterm and full-term infants at 5 and 12 months of age to longitudinally study brain electrical activity as a function of perception of structured forward optic flow, structured reversed optic flow, and non-structured random visual motion. (bibsys.no)
  • In full-term infants, VEP results revealed a significant decrease in latencies for forward and reversed optic flow, but not for random visual motion with age. (bibsys.no)
  • At 12 months, full-term infants were also found to significantly differentiate between the three motion conditions, with shortest latencies for forward optic flow, and longest latencies for random visual motion. (bibsys.no)
  • When the TSEs of the three motion conditions were compared to the TSEs of a static non-flow control condition, full-term infants at 5 and 12 months showed significant differences in induced activity. (bibsys.no)
  • Early visual experience and the receptive-field organization of optic flow processing interneurons in the fly motion pathway", Visual neuroscience , vol. 18, 2001, pp. 1-8. (uni-bielefeld.de)
  • There he worked mainly in the psychophysics of human visual perception, on phenomena surrounding higher-order motion aftereffects, visual search and attention in the real world, visual flow fields, and eye movements. (wikipedia.org)
  • Asymmetrical masking between radial and parallel motion flow in transparent displays. (wikipedia.org)
  • In other words, motion can be derived without using retinal flow, instead using optical flow understood in a more abstract sense. (wikipedia.org)
  • Motion camouflage Optic flow Gibson, J. J. (2014). (wikipedia.org)
  • One major source of visual information when determining self-motion is optic flow. (wikipedia.org)
  • Optical flow or optic flow is the pattern of apparent motion of objects, surfaces, and edges in a visual scene caused by the relative motion between an observer and a scene. (wikipedia.org)
  • The term optical flow is also used by roboticists, encompassing related techniques from image processing and control of navigation including motion detection, object segmentation, time-to-contact information, focus of expansion calculations, luminance, motion compensated encoding, and stereo disparity measurement. (wikipedia.org)
  • The optical flow methods try to calculate the motion between two image frames which are taken at times t and t + Δ t {\displaystyle t+\Delta t} at every voxel position. (wikipedia.org)
  • Motion estimation and video compression have developed as a major aspect of optical flow research. (wikipedia.org)
  • The application of optical flow includes the problem of inferring not only the motion of the observer and objects in the scene, but also the structure of objects and the environment. (wikipedia.org)
  • The principal form of motion camouflage, and the type generally meant by the term, involves an attacker's mimicking the optic flow of the background as seen by its target. (wikipedia.org)
  • First discovered in hoverflies in 1995, motion camouflage by minimising optic flow has been demonstrated in another insect order, dragonflies, as well as in two groups of vertebrates, falcons and echolocating bats. (wikipedia.org)
  • This is not the same as moving straight towards the target (classical pursuit): that results in visible sideways motion with a readily detectable difference in optic flow from the background. (wikipedia.org)
  • radial
  • In Experiment 2 we demonstrate that the results of Experiment 1 are consistent with a positively weighted vector sum of the effects seen when viewing the probe together with individual radial and planar flow fields. (arvojournals.org)
  • Assessing
  • Abstract We have recently suggested that neural flow parsing mechanisms act to subtract global optic flow consistent with observer movement to aid in detecting and assessing scene-relative object movement.Here, we examine whether flow parsing can occur independently from heading estimation. (arvojournals.org)
  • estimate
  • If flow parsing depends upon a prior estimate of heading then the perceived trajectory should reflect global subtraction of a field consistent with the heading experienced under the OFI. (arvojournals.org)
  • spectroscopy
  • In the present contribution, the theoretical relationship existing between the blood flow index measured by diffuse correlation spectroscopy and single-photon laser-Doppler flowmetry (SP-LDF) is investigated. (readbyqxmd.com)
  • patterns
  • We tested whether human observers maintain ideal patterns of information use across the visual field (VF) in determining direction of heading (DOH) from optic flow. (arvojournals.org)
  • Six participants aged 18-22 fixated centrally while monocularly viewing flow patterns simulating straight-line movement in depth through a 3D cloud of dots. (arvojournals.org)
  • While the ideal observer model explains some of the complex patterns human observers exhibit in weighing information across the visual field, it did not predict their bias to rely on the upper half of the visual field in determining direction of heading from optic flow. (arvojournals.org)
  • measurements
  • Flow was calculated on the basis of these noninvasive measurements and demonstrated an average decrease of 74% in optic atrophy. (arvojournals.org)
  • This study also demonstrates that the noninvasive measurements of blood flow are substantiated by histologic evaluation of microsphere distribution. (arvojournals.org)
  • humans
  • In humans, during an artificial IOP rise using a suction cup method the ONH blood flow maintains almost constant until IOP reaches 40-55 mmHg. (clinicaltrials.gov)
  • field
  • One way to assess the accuracy of the flow estimation is to synthesise the second image by warping the first with a known flow field, then seeing if we can recover the parameters of the field. (mathworks.com)
  • Bumblebees measure optic flow for position and speed control flexibly within the frontal visual field. (lu.se)
  • Previously, it has been shown that when bumblebees encounter sudden changes in the proximity to nearby surfaces - as indicated by a change in the magnitude of optic flow on each side of the visual field - they adjust their flight speed well before the change, suggesting that they measure optic flow for speed control at low visual angles in the frontal visual field. (lu.se)
  • edges
  • We can see whether the flow that has been found maps the first image onto the second, by displaying edges. (mathworks.com)
  • Here, the green edges are the original first image, the blue edges are the second image, and the red edges are the first image after warping by the flow. (mathworks.com)
  • closer
  • It will, for example, fly down the middle of a tunnel, because if it flew closer to one side the optic flow would appear to be greater. (wikipedia.org)
  • Barron
  • John L. Barron, David J. Fleet, and Steven Beauchemin provide a performance analysis of a number of optical flow techniques. (wikipedia.org)
  • glaucoma
  • The model suggests that the raised intraocular pressures present in glaucoma are adequate to produce significant intracellular fluid flow. (cpib.ac.uk)
  • direction
  • These results suggest that flow parsing is not necessarily dependent on prior estimation of heading direction. (arvojournals.org)
  • Optic flow not only indicates whether an agent is moving but in which direction and at what relative speed. (wikipedia.org)
  • In the direction of the train, the visual world would appear to flow in the same direction and expand. (wikipedia.org)
  • fields
  • It would be possible to refine this experimentally, given an error measure, a set of images, and a set of flow fields. (mathworks.com)
  • eyes
  • When avoiding objects, the bee will tend to take the optimal path because it will 'balance' the rate of the optic flow between the eyes. (wikipedia.org)
  • image
  • The flow is estimated as for the real image pair. (mathworks.com)
  • Optical flow was used by robotics researchers in many areas such as: object detection and tracking, image dominant plane extraction, movement detection, robot navigation and visual odometry. (wikipedia.org)
  • order
  • As a result, the first-order flow provides an approximation to the true flow, though it does not capture its details or exact form. (mathworks.com)
  • We do not expect exact overlap because the first-order flow can only be an approximate, smooth, model of the true flow. (mathworks.com)
  • SFM from 2nd order optic flow and perspective effects. (wikipedia.org)
  • maximum
  • the smoothing constant) needs to be set either using some prior knowledge of the likely maximum flow speed, or by experiment. (mathworks.com)
  • another
  • To find the optical flow another set of equations is needed, given by some additional constraint. (wikipedia.org)
  • Another laser beam (at either ~248 nm or ~308 nm) in the form of a sheet is also passed through the flow in the same plane as the grid. (wikipedia.org)
  • complex
  • Srinivasan has shown that many ostensibly complex flight behaviours can be attributed to the tendency of the bee to keep optic flow constant. (wikipedia.org)
  • fiber
  • Photons play a central role in information technologies such as fiber optics the way electrons do in electronics. (pearltrees.com)
  • Post-installed fiber optic pressure sensors on subsea production risers for severe slugging control" (PDF). (wikipedia.org)
  • needs update] The company helped to get the modern telecommunications industry off the ground by running fiber optic cable through its decommissioned pipelines. (wikipedia.org)
  • Extech Instruments has two divisions: Instruments Thermal Imager Multimeters (DMM) Clamp Meters Air flow meters Light meters Sound Meters Tachometers Pressure meters Calibrators Water quality meters Moisture meters Humidity meters Contact and Non-Contact Thermometers (IR) Power Supplies Fiber optic meters EMF Strength Meters Portable Printers Extech Instruments's handheld test instruments are sold through a network of national catalog houses, regional stocking distributors and international distributors. (wikipedia.org)
  • measurement
  • This is a whole-cell current clamp recording of a neuron firing due to it being depolarized by current injection Definition and scope[edit] Classical electrophysiological techniques[edit] Electrophysiology is the science and branch of physiology that pertains to the flow of ions in biological tissues and, in particular, to the electrical recording techniques that enable the measurement of this flow. (pearltrees.com)
  • electric
  • An electrostatic analyzer or ESA is an instrument used in ion optics that employs an electric field to allow the passage of only those ions or electrons that have a given specific energy. (wikipedia.org)
  • The steel is magnetised by a large electric current that flows in the coils of wire wrapped around the poles. (wikipedia.org)
  • light
  • By positioning Light tubes strategically, using filters and other light optics means, the SE can again be separated from the BSE and corresponding images formed. (wikipedia.org)
  • Network
  • Other techniques that address congestion include priority schemes which transmit some packets with higher priority ahead of others and the explicit allocation of network resources to specific flows through the use of admission control. (wikipedia.org)
  • The optimal rate allocation then satisfies max x ∑ i U ( x i ) {\displaystyle \max \limits _{x}\sum _{i}U(x_{i})} such that R x ≤ c {\displaystyle Rx\leq c} The Lagrange dual of this problem decouples, so that each flow sets its own rate, based only on a "price" signalled by the network. (wikipedia.org)
  • rate
  • This is typically accomplished by reducing the rate of packets and it should not be confused with flow control, which prevents the sender from overwhelming the receiver. (wikipedia.org)
  • Let x i {\displaystyle x_{i}} be the rate of flow i {\displaystyle i} , c l {\displaystyle c_{l}} be the capacity of link l {\displaystyle l} , and r l i {\displaystyle r_{li}} be 1 if flow i {\displaystyle i} uses link l {\displaystyle l} and 0 otherwise. (wikipedia.org)
  • Hydrodynamic slugging is caused by gas flowing at a fast rate over a slower flowing liquid phase. (wikipedia.org)
  • Whether a slug is able to reach the outlet of the pipeline depends on the rate at which liquids are added to the slug at the front (i.e. in the direction of flow) and the rate at which liquids leave the slug at the back. (wikipedia.org)
  • together
  • Characteristics of the final separated beams as observed in the 15- inch hydrogen bubble chamber are given together with a detailed description of the beam optics and apparatas. (unt.edu)
  • Pipelines that transport both gas and liquids together, known as two-phase flow, can operate in a flow regime known as slugging flow or slug flow. (wikipedia.org)
  • techniques
  • Via numerical techniques, we analyze the impact of two different applied temperature gradients, 10 K/cm and 30 K/cm, on the flow, temperature, tellurium distribution, and undercooling during growth with and without applied ACRT. (spiedigitallibrary.org)