Directional Edge Boxes: Exploiting Inner Normal Direction Cues for Effective Object Proposal Generation

2017 ◽  
Vol 32 (4) ◽  
pp. 701-713 ◽  
Author(s):  
Xiang Bai ◽  
Zheng Zhang ◽  
Hong-Yang Wang ◽  
Wei Shen
Keyword(s):  
Normal Direction ◽  
Object Proposal ◽  
Directional Edge

The effects of surface absorbed monolayer microdiffraction patterns

1988 ◽  
Vol 46 ◽  
pp. 680-681
Author(s):  
M. Pan ◽  
J.M. Cowley
Keyword(s):  
Surface Potential ◽  
Electron Probe ◽  
Potential Distribution ◽  
Crystal Surface ◽  
Normal Direction ◽  
Surface Image ◽  
Extended Surface ◽  
Gas Molecules ◽  
Surface Nature ◽  
Electron Microdiffraction

Electron microdiffraction patterns, obtained when a small electron probe with diameter of 10-15 Å is directed to run parallel to and outside a flat crystal surface, are sensitive to the surface nature of the crystals. Dynamical diffraction calculations have shown that most of the experimental observations for a flat (100) face of a MgO crystal, such as the streaking of the central spot in the surface normal direction and (100)-type forbidden reflections etc., could be explained satisfactorily by assuming a modified image potential field outside the crystal surface. However the origin of this extended surface potential remains uncertain. A theoretical analysis by Howie et al suggests that the surface image potential should have a form different from above-mentioned image potential and also be smaller by several orders of magnitude. Nevertheless the surface potential distribution may in practice be modified in various ways, such as by the adsorption of a monolayer of gas molecules.

scholarly journals Numerical Simulations of Novel Conning Designs for Future Super-Large Wind Turbines

2020 ◽  
Vol 11 (1) ◽  
pp. 147
Author(s):  
Zhenye Sun ◽  
Weijun Zhu ◽  
Wenzhong Shen ◽  
Qiuhan Tao ◽  
Jiufa Cao ◽  
...  
Keyword(s):  
Wind Turbines ◽  
Cone Angle ◽  
Angle Of Attack ◽  
Normal Direction ◽  
Velocity Decomposition ◽  
New Concepts ◽  
Blade Tip ◽  
Tip Position ◽  
Large Wind ◽  
Lower Angle

In order to develop super-large wind turbines, new concepts, such as downwind load-alignment, are required. Additionally, segmented blade concepts are under investigation. As a simple example, the coned rotor needs be investigated. In this paper, different conning configurations, including special cones with three segments, are simulated and analyzed based on the DTU-10 MW reference rotor. It was found that the different force distributions of upwind and downwind coned configurations agreed well with the distributions of angle of attack, which were affected by the blade tip position and the cone angle. With the upstream coning of the blade tip, the blade sections suffered from stronger axial induction and a lower angle of attack. The downstream coning of the blade tip led to reverse variations. The cone angle determined the velocity and force projecting process from the axial to the normal direction, which also influenced the angle of attack and force, provided that correct inflow velocity decomposition occurred.

Numerical Simulation of the Effects of Preheating on Electron Beam Additive Manufactured Ti-6Al-4V Build Plate

2016 ◽  
Vol 879 ◽  
pp. 274-278 ◽  
Author(s):  
Jun Cao ◽  
Philip Nash
Keyword(s):  
Numerical Simulation ◽  
Residual Stress ◽  
Finite Element ◽  
Electron Beam ◽  
Cross Section ◽  
Element Model ◽  
Normal Direction ◽  
Thermal Residual Stresses ◽  
Longitudinal Residual Stress ◽  
Middle Cross Section

In an earlier study, a 3-D thermomechanical coupled finite element model was built and experimentally validated to investigate the evolution of the thermal residual stresses and distortions in electron beam additive manufactured Ti-6Al-4V build plates. In this study, an investigation using this robust and accurate model was focused on an efficient preheating method, in which the electron beam quickly scanned across the substrate to preheat the build plate prior to the deposition. Various preheat times, beam powers, scan rates, scanning paths and cooling times (between the end of current preheat scan/deposition layer and the beginning of the next preheat scan/deposition layer) were examined, and the maximum distortion along the centerline of the substrate and the maximum longitudinal residual stress along the normal direction on the middle cross-section of the build plate were quantitatively compared. The results show that increasing preheat times and beam powers could effectively reduce both distortion and residual stress for multiple layers/passes components.

scholarly journals Effect of ball collision direction on a wet mechanochemical reaction

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Takahiro Kozawa ◽  
Kayo Fukuyama ◽  
Kizuku Kushimoto ◽  
Shingo Ishihara ◽  
Junya Kano ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Reaction Rates ◽  
Tangential Component ◽  
Normal Direction ◽  
Mechanochemical Reaction ◽  
Precipitation Mechanism ◽  
The Impact ◽  
Mechanochemical Reactions ◽  
Ball Motion

AbstractMechanochemical reactions can be induced in a solution by the collision of balls to produce high-temperature and high-pressure zones, with the reactions occurring through a dissolution–precipitation mechanism due to a change in solubility. However, only a fraction of the impact energy contributes to the mechanochemical reactions, while the rest is mainly consumed by the wear of balls and the heat generation. To clarify whether the normal or tangential component of collisions makes a larger contribution on the reaction, herein we studied the effect of collision direction on a wet mechanochemical reaction through combined analysis of the experimental reaction rates and simulated ball motion. Collisions of balls in the normal direction were found to contribute strongly to the wet mechanochemical reaction. These results could be used to improve the synthesis efficiency, predict the reaction, and lower the wear in the wet mechanochemical reactions.

scholarly journals Detecting the normal-direction in automated aircraft manufacturing based on adaptive alignment

2020 ◽  
Vol 103 (4) ◽  
pp. 003685042098121
Author(s):  
Ying Zhang ◽  
Hongchang Ding ◽  
Changfu Zhao ◽  
Yigen Zhou ◽  
Guohua Cao
Keyword(s):  
Calibration Method ◽  
Adaptive Method ◽  
Normal Direction ◽  
Detection Accuracy ◽  
Average Deviation ◽  
Important Indicator ◽  
Aircraft Manufacturing ◽  
Direction Detection ◽  
Hole Making ◽  
Vertical Accuracy

In aircraft manufacturing, the vertical accuracy of connection holes is important indicator of the quality of holes making. Aircraft products have high requirements for the vertical accuracy of holes positions. When drilling and riveting are performed by an automatic robotic system, assembly errors, bumps, offsets and other adverse conditions, can affects the accuracy of manufacturing and detection, and in turn the fatigue performance of the entire structure. To solve this problem, we proposed a technology for detecting the normal-direction based on the adaptive alignment method, built a mathematical model for posture alignment, and studied the calibration method and mechanism of the detection device. Additionally, we investigated techniques for error compensation using an electronic theodolite and other devices when the adaptive method is used for detection. In verification experiments of the method, multiple sets of results demonstrated that the key technical indicators are as follows: normal accuracy <0.5°, average deviation after correction =0.0667°. This method can effectively compensate the errors affecting hole making work in automated manufacturing, and further improve the positioning accuracy and normal-direction detection accuracy of the robot.

Structural characterization of laser ablated epitaxial (Ba0.5Sr0.5)TiO3 thin films on MgO(001) by synchrotron x-ray scattering

1999 ◽  
Vol 14 (7) ◽  
pp. 2905-2911 ◽  
Author(s):  
Sangsub Kim ◽  
Tae Soo Kang ◽  
Jung Ho Je
Keyword(s):  
Thin Films ◽  
Early Stage ◽  
Lattice Parameter ◽  
Normal Direction ◽  
X Ray ◽  
X Ray Scattering ◽  
Surface Normal ◽  
Out Of Plane ◽  
Axis Parallel ◽  
Ray Scattering

Epitaxial (Ba0.5Sr0.5) TiO3 thin films of two different thickness (∼25 and ∼134 nm) on MgO(001) prepared by a pulsed laser deposition method were studied by synchrotron x-ray scattering measurements. The film grew initially with a cube-on-cube relationship, maintaining it during further growth. As the film grew, the surface of the film became significantly rougher, but the interface between the film and the substrate did not. In the early stage of growth, the film was highly strained in a tetragonal structure (c/a = 1.04) with the longer axis parallel to the surface normal direction. As the growth proceeded further, it relaxed to a cubic structure with the lattice parameter near the bulk value, and the mosaic distribution improved significantly in both in- and out-of-plane directions. The thinner film (∼25 nm) showed only one domain limited mainly by the film thickness, but the thicker film (∼134 nm) exhibited three domains along the surface normal direction.

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