CIOSOS: Combined Idiomatic-Ontology Based Sentiment Orientation System for Trust Reputation in E-commerce

Author(s):  
Hasnae Rahimi ◽  
Hanan EL Bakkali
Author(s):  
Jihad Adib ◽  
Hicham Moutachaouik ◽  
Abdelaziz Marzak ◽  
Mustapha Hain
Keyword(s):  

Author(s):  
V.P. Podchezertsev ◽  
S.V. Topilskaya

The article discusses criteria for selecting the vibration protection for the spacecraft inertial orientation system. The considered vibration protection system allows providing acceptable amplitude acceleration for the gyroscopic device sensitive elements under vibration impact on the device body during the spacecraft launching and high angular stability of the position of the sensitive elements relative to the inertial coordinate system during a long period of operation (15 years) in orbit. The proposed vibration protection system consists of shock absorbers (springs) with stable high elastic characteristics under all factors of operation in the outer space and dynamic vibration dampers. The article presents a method for determining the parameters of dynamic vibration dampers taking into account the characteristics of the shock absorber, critical for the damping system of an inertial device. The proposed method for adjusting dynamic vibration dampers consists in suppressing vibrations at the natural frequency f1 of the shock absorption system and providing acceptable values of the gain coefficients of the structure resonant vibration amplitudes near the natural frequency f1. Certain characteristics of the damping system allow realizing the permissible vibration amplification coefficients at resonance, without significantly affecting the level of vibration suppression in the natural frequency zone of the vibration protection object


Author(s):  
Haipeng Kuang ◽  
Lina Zheng ◽  
Guoqin Yuan ◽  
Jianjun Sun ◽  
Zhuang Zhang

Image misalignment during image stitching is a common issue for the mechanically stitched CCDs in the aerial cameras due to the relative image motion between CCDs. In this paper, we analyze the error in imaging stitching for the mechanically stitched CCDs and propose a compensation method based on position and orientation system (POS). First, the imaging relationship of overlapping pixels in mechanical stitching is analyzed. The imaging model of adjacent CCD is constructed according to the collinear equation. The effects of stitching staggered distance, carrier attitude change and flight speed on the image mosaic of overlapping areas are given. Monte Carlo algorithm is used to analyze the statistical value of image mosaic error in overlapping area under typical working conditions. Then, a geometric correction method based on POS recording of external orientation elements of adjacent CCD imaging is proposed. The overlapping area stitching error is reduced from 14.9 pixels to 0.4 pixels which meets the engineering requirements. The mechanical stitching mathematical model, analysis and correction method established in this paper have strong engineering and application significance for mechanical stitching of aerial cameras.


Sign in / Sign up

Export Citation Format

Share Document