Affine Reconstruction Based on Parallel Plane and Infinity Point

2011 ◽  
Vol 255-260 ◽  
pp. 2272-2275
Author(s):  
Yue Zhao ◽  
Xiao Hua Hu
Keyword(s):  
Computer Simulation ◽  
Reconstruction Algorithm ◽  
Parallel Plane ◽  
Good Precision ◽  
Affine Shape ◽  
Plane Homography ◽  
Plane At Infinity

Affine reconstruction is to restore the affine shape of the object. Generally, there are two ways of achieving, one is to determine the plane at infinity, another is to determine the plane homography. Using the homography which had determined the plane at infinity achieve affine reconstruction. In this paper, firstly give out the homography of infinity plane and the algorithm of affine reconstruction, then proved: if the scene contains a set of parallel planes and a infinity point, the homography of infinity plane can be obtained and affine reconstruction can be linearly got in the scene. Computer simulation and real experiments show that the linear affine reconstruction algorithm is correct, and the approach has a good precision.

Angle Measurement for Meter-Wave Radar Based on Mainlobe Multipath Jamming Suppression

2013 ◽  
Vol 347-350 ◽  
pp. 257-262 ◽  
Author(s):  
Ying Jun Zhao ◽  
Rong Feng Li ◽  
Yong Liang Wang ◽  
Wei Jian Liu
Keyword(s):  
Computer Simulation ◽  
Angle Measurement ◽  
Good Precision ◽  
New Approach ◽  
Wave Radar ◽  
Multipath Signal

When detecting low-attitude targets, the angular accuracy of the meter-wave radar will descend because of the multipath reflecting from ground. Since the multipath signal can be regarded as a multipath jamming coming from the mainlobe, we propose an angle measurement based on the mainlobe multipath jamming suppression. The weight of the new approach is obtained through certain constraints on the sum-difference beams, which can suppress the jamming and keep the curve of the monopulse ratio unchanged. Then form sum-difference beams and calculate the ratio of the monopulse ratio of the target. Finally, obtain the angle of the target through the determination of the smallest difference between the monopulse ratio of the target and the quiescent monopulse ratio. The method proposed in this paper can preserve good precision of the measurement angle. The result is verified by computer simulation.

Adaptive Monopulse Angle Measurement for Meter-Wave Radar Based on Differential Constraints Technique

2013 ◽  
Vol 846-847 ◽  
pp. 812-817 ◽  
Author(s):  
Zhao Ying Jun ◽  
Li Rong Feng ◽  
Wang Yong Liang ◽  
Liu Wei Jian
Keyword(s):  
Computer Simulation ◽  
Angle Measurement ◽  
Good Precision ◽  
New Approach ◽  
Differential Constraints ◽  
Wave Radar ◽  
Multipath Signals

When detecting low-attitude targets, the angular accuracy of the meter-wave radar will descend because of the multipath reflecting from ground. Since multipath signals can be regarded as multipath jamming coming from the mainlobe, we propose an angle measurement based on the mainlobe multipath jamming suppression through differential constraints technique. The weight of the new approach is obtained through certain constraints on the sum-difference beams, which can suppress the jamming and keep the curve of the monopulse ratio unchanged simultaneously. Then form sum-difference beams and calculate the ratio of the monopulse ratio of the target. Finally, obtain the angle of the target through the determination of the smallest difference between the monopulse ratio of the target and the quiescent monopulse ratio. The method proposed in this paper can preserve good precision of the measurement angle. The result is verified by computer simulation.

Unbiased estimation of particle number and sizes using the new stereological tools: the disector, the fractionator, the selector, and the nucleator — or just point-sampled intercepts

1988 ◽  
Vol 46 ◽  
pp. 428-429
Author(s):  
H.J.G. Gundersen
Keyword(s):  
Particle Number ◽  
Small Distance ◽  
Parallel Plane ◽  
Unbiased Estimation ◽  
Severe Problem ◽  
New Era ◽  
Size And Shape ◽  
Distinct Property ◽  
Sectioned Tissue

Previously, all stereological estimation of particle number and sizes were based on models and notoriously gave biased results, were very inefficient to use and difficult to justify. For all references to old methods and a direct comparison with unbiased methods see recent reviews.The publication in 1984 of the DISECTOR, the first unbiased stereological probe for sampling and counting 3—D objects irrespective of their size and shape, signalled the new era in stereology — and give rise to a number of remarkably simple and efficient techniques based on its distinct property: It is the only known way to obtain an unbiased sample of 3-D objects (cells, organelles, etc). The principle is simple: within a 2-D unbiased frame count or sample only cells which are not hit by a parallel plane at a known, small distance h.The area of the frame and h must be known, which might sometimes in itself be a problem, albeit usually a small one. A more severe problem may arise because these constants are known at the scale of the fixed, embedded and sectioned tissue which is often shrunken considerably.

Characterization of Modulated Structure Through Structure Images and their Computer Simulation

1990 ◽  
Vol 48 (1) ◽  
pp. 70-71
Author(s):  
Kiyomichi Nakai ◽  
Yusuke Isobe ◽  
Chiken Kinoshita ◽  
Kazutoshi Shinohara
Keyword(s):  
Computer Simulation ◽  
High Resolution ◽  
Spherical Aberration ◽  
High Resolution Electron Microscopy ◽  
Basic Mechanism ◽  
Objective Lens ◽  
Specimen Thickness ◽  
Transmitted Beam ◽  
Modulated Structure ◽  
Resolution Electron

Induced spinodal decomposition under electron irradiation in a Ni-Au alloy has been investigated with respect to its basic mechanism and confirmed to be caused by the relaxation of coherent strain associated with modulated structure. Modulation of white-dots on structure images of modulated structure due to high-resolution electron microscopy is reduced with irradiation. In this paper the atom arrangement of the modulated structure is confirmed with computer simulation on the structure images, and the relaxation of the coherent strain is concluded to be due to the reduction of phase-modulation.Structure images of three-dimensional modulated structure along <100> were taken with the JEM-4000EX high-resolution electron microscope at the HVEM Laboratory, Kyushu University. The transmitted beam and four 200 reflections with their satellites from the modulated structure in an fee Ni-30.0at%Au alloy under illumination of 400keV electrons were used for the structure images under a condition of the spherical aberration constant of the objective lens, Cs = 1mm, the divergence of the beam, α = 3 × 10-4 rad, underfocus, Δf ≃ -50nm and specimen thickness, t ≃ 15nm. The CIHRTEM code was used for the simulation of the structure image.

Averting robo-bees: why free-flying robotic bees are a bad idea

2019 ◽  
Vol 3 (6) ◽  
pp. 723-729
Author(s):  
Roslyn Gleadow ◽  
Jim Hanan ◽  
Alan Dorin
Keyword(s):  
Climate Change ◽  
Computer Simulation ◽  
Food Security ◽  
European Countries ◽  
Plant Interactions ◽  
Plant Insect Interactions ◽  
Native Habitat ◽  
Insect Pollinators ◽  
Insect Interactions

Food security and the sustainability of native ecosystems depends on plant-insect interactions in countless ways. Recently reported rapid and immense declines in insect numbers due to climate change, the use of pesticides and herbicides, the introduction of agricultural monocultures, and the destruction of insect native habitat, are all potential contributors to this grave situation. Some researchers are working towards a future where natural insect pollinators might be replaced with free-flying robotic bees, an ecologically problematic proposal. We argue instead that creating environments that are friendly to bees and exploring the use of other species for pollination and bio-control, particularly in non-European countries, are more ecologically sound approaches. The computer simulation of insect-plant interactions is a far more measured application of technology that may assist in managing, or averting, ‘Insect Armageddon' from both practical and ethical viewpoints.

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