AERIAL SURVEILLANCE FOR VEHICLE DETECTION USING DBN AND CANNY EDGE DETECTOR

We present an automatic vehicle detection system for aerial surveillance in this paper. In this system, we escape from the stereotype and existing frameworks of vehicle detection in aerial surveillance, which are either region based or sliding window based. We design a pixel wise classification method for vehicle detection. The novelty lies in the fact that, in spite of performing pixel wise classification, relations among neighboring pixels in a region are preserved in the feature extraction process. We consider features including vehicle colors and local features. For vehicle color extraction, we utilize a color transform to separate vehicle colors and non-vehicle colors effectively. For edge detection, we apply moment preserving to adjust the thresholds of the Canny edge detector automatically, which increases the adaptability and the accuracy for detection in various aerial images. Afterward, a dynamic Bayesian network (DBN) is constructed for the classification purpose. We convert regional local features into quantitative observations that can be referenced when applying pixel wise classification via DBN. Experiments were conducted on a wide variety of aerial videos. The results demonstrate flexibility and good generalization abilities of the proposed method on a challenging data set with aerial surveillance images taken at different heights and under different camera angles

Assessment of Laws of the Wall During Flame–Wall Interaction of Premixed Flames Within Turbulent Boundary Layers

\ua9 The Author(s) 2024. The validity of the usual laws of the wall for Favre mean values of the streamwise velocity component and temperature for non-reacting flows has been assessed for turbulent premixed flame-wall interaction using Direct Numerical Simulation (DNS) data. Two different DNS databases corresponding to friction velocity-based Reynolds number of 110 and 180 representing unsteady head-on quenching of statistically planar flames within turbulent boundary layers have been considered. The usual log-law based expressions for the Favre mean values of the streamwise velocity and temperature for the inertial layer have been found to be inadequate at capturing the corresponding variations obtained from DNS data. The underlying assumptions of constant shear stress and the equilibrium of production and dissipation of turbulent kinetic energy underpinning the derivation of the usual log-law for the mean streamwise velocity have been found to be rendered invalid within the usual inertial layer during flame-wall interaction for both cases considered here. The heat flux does not remain constant within the usual inertial layer, and the turbulent flux of temperature exhibits counter-gradient transport within the so-called inertial layer for the cases considered in this work. These render the assumptions behind the derivation of the usual log-law for temperature to be invalid for application to turbulent flame-wall interaction. It has been found that previously proposed empirical modifications to the existing laws of the wall, which account for density and kinematic viscosity variations with temperature, do not significantly improve the agreement with the corresponding DNS data in the inertial layer and the inaccurate approximations for the kinematic viscosity compensated wall normal distance and the density compensated streamwise velocity component contribute to this disagreement. The DNS data has been utilised here to propose new expressions for the kinematic viscosity compensated wall normal distance and the density compensated streamwise velocity component, which upon using in the empirically modified law of wall expressions have been demonstrated to provide reasonable agreement with DNS data

Perturbation solutions of fifth order oscillatory nonlinear systems

Oscillatory systems play an important role in the nature. Many engineering problems and physical systems of fifth degrees of freedom are oscillatory and their governing equations are fifth order nonlinear differential equations. To investigate the solution of fifth order weakly nonlinear oscillatory systems, in this article the Krylov–Bogoliubov–Mitropolskii (KBM) method has been extended and desired solution is found. An example is solved to illustrate the method. The results obtain by the extended KBM method show good agreement with those obtained by numerical method

Lateral tibial condyle reconstruction by pedicled vascularized fibular head graft: Long-term result

The technique of pedicled vascularized fibular graft for lateral tibial condyle reconstruction after en bloc resection of aggressive giant cell tumours was described by SP Chow et al. Early follow-up of two patients was presented in 1986. We present the 25 years follow-up of one patient with a literature review of alternative present day treatment options. The patient maintained community ambulant status despite developing late stage osteoarthritis. Although this procedure is performed rarely, it remains an alternative to the more sophisticated treatment options making it a useful method in centres with limited facilities and expertise. © 2011 The Author(s).published_or_final_versio

The Pattern of Quality Education: A Comparative Analysis on Public and Private Universities in Bangladesh

From the beginning of the last decade the private universities have been playing massive role at tertiary education in Bangladesh. It has almost changed the total scenario, story line of the education system of the last 200 years. Private universities started with a vision, goal and amid so many barriers and obstacles. It has also sound attainment and contribution to the nation. Quality education is a prerequisite for sustainable development. For finding the determinants of quality tertiary education, studies suggest inclusion of relevant variables, as the customers are well diversified with students, their parents and guardians, and academic and administrative staff- each having different needs and objectives. Thus, this paper tries to incorporate forty nine  “Quality Characteristics” which previously found significant by various studies with a few uniquely appropriate local characteristics. The results show that the quality of private university education mainly depends upon the competence of their academic and administrative staff, the content of their curriculum, reliability of the institution, and the attitude of their staff. Keywords: Quality Dimensions, Customers, Public Universities, Private Universitie