3D Target Scale Estimation and Target Feature Separation for Size Preserving Tracking in PTZ Video

To achieve size preserving tracking, in addition to controlling the camera’s pan and tilt motions to keep the object of interest in the camera’s field of view (FOV), the camera’s focal length is adjusted automatically to compensate for the changes in the target’s image size caused by the relative motion between the camera and the target. The estimation accuracy of these changes determines the effectiveness of the resulting zoom control. The existing method of choice for real-time target scale estimation applies structure from motion (SFM) based on the weak perspective projection model. In this paper we propose a target scale estimation algorithm with a linear solution based on the more advanced paraperspective projection model, which improves the accuracy of scale estimation by considering center offset. Another key issue in SFM based algorithms is the separation of target and background features, especially when composite camera (pan/tilt/zoom) and target motions are involved. This paper designs a fast target feature separation/grouping algorithm, the 3D affine shape method. The resulting separation automatically adapts to the target’s 3D geometry and motion and is able to accommodate a large amount of off-plane rotation, which most existing separation/grouping algorithms find difficult to achieve. Experimental results illustrate the effectiveness of the proposed scale estimation and feature separation algorithms in tracking translating and rotating objects with a PTZ camera while preserving their sizes. In comparison with the leading size preserving tracking algorithm described by Tordoff and Murray, our algorithm is able to reduce the cumulative tracking error significantly from 17.4% to 3.3%.     

Development of an odor wheel classification scheme for wastewater.

Overall, in the air pollution control field, odor concentration and intensity as well as hedonic rating have been well studied to the point where some level of standardization is being developed or is already in place. However, there has been no standardization with respect to odor quality characterization. There is now sufficient understanding of the types of odorous compounds that can arise from wastewater treatment processes to develop an odor classification scheme. This article presents the first wastewater odor wheel or classification scheme that should form the foundation for the evolution of odor quality data reporting with links to chemical causes.     

Finite difference discretization of the extended Fisher-Kolmogorov equation in two dimensions

Approximate solutions are considered for the extended Fisher-Kolmogorov (EFK) equation in two space dimension with Dirichlet boundary conditions by a Crank-Nicolson type finite difference scheme. A priori bounds are proved using Lyapunov functional. Further, existence, uniqueness and convergence of difference solutions with order O(h²+k²) in the L^∞-norm are proved. Numerical results are also given in order to check the properties of analytical solutions.     

Modelling of heat and mass transfer in a tunnel dryer

This work presents a numerical model for heat and mass transfer of granular products in a fixed-bed tunnel dryer. The drying process is simulated under real operating conditions based on a thin layer model and experimental drying kinetics. A simplified heat and mass transfer numerical model is developed based on the governing equations and the drying rate of a thin layer bed of granular products.The obtained system of non-linear partial differential equations is numerically solved by a finite volume method. The turbulent airflow and granular bed convection coefficient as well as the effective conductivity are estimated using the turbulent airflow over flat-plate correlations. Simulations are compared with experimental data from drying of grapes in a thin layer model.In order to study the effects of the air inlet conditions on the relative moisture content and the drying time and therefore to optimise the tunnel dryer operation, the influences of different parameters essentially the air flow characteristics and the fixed-bed dryer length are examined. The numerical code allows establishing the drying front propagation for several operating conditions.     

New lignocellulosic fibres-reinforced composite materials: A stepforward in the valorisation of the Posidonia oceanica balls

In this work, new lignocellulosic particles obtained from Posidonia oceanica were studied to reinforce a commercial biodegradable thermoplastic matrix. First, these reinforcing fillers were characterised by Fourier-transform infrared (FT-IR) and X-ray photoelectron (XPS) spectroscopies. Then, they were used to prepare several composite films using BIOPLAST GF 106 matrix. Different P. oceanica fragment loadings, namely 0%, 10%, 20% and 30% (w/w with respect to the matrix) were investigated. The morphology of the ensuing materials was assessed by scanning electron microscopy (SEM), whereas their thermal and mechanical properties were studied by differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and tensile tests. The obtained results showed that P. oceanica-based particles enhanced the thermo-mechanical properties of the thermoplastic matrix.     

Formation,rapid thermal oxidation and passivation of solar grade silicon nanowires for advanced photovoltaic applications

Uniform and regular silicon nanowires (SiNWs) arrays are fabricated on both sides of solar grade silicons (SiGS) by silver assist-electrochemical etching. SiNWs arrays exhibit an excellent antireflection character with an overall reflectance of 2% in the range from 300 to 1000 nm. More importantly, the effective lifetimes of the symmetric SiNWs/Si structures decreased due to the high densities of dangling bonds and surface defects. Surface passivation to overcome lifetime degradation is realized by means of rapid thermal oxidation (RTO). Following rapid oxidation, Fourier Transform Infrared spectroscopy reveals that oxygen diffusion is enhanced inside silicon nanowires where the morphological structure is preserved during RTO. Moreover, it is shown that even the rapid thermal oxidation process is not effective to recover initial τ_eff due to the high density of imperfections involved during nanowires formation and the contamination level induced by silver. The interdiffusion between residual silver and metal contaminants in the core of the nanowire can probably limit the passivation effect due to the segregation of metal atoms at SiO₂ and to the redistribution of both impurities across the wire.     

Gray-level grouping (GLG): an automatic method for optimized image contrast enhancement--Part II: the variations.

This is Part II of the paper, "Gray-Level Grouping (GLG): an Automatic Method for Optimized Image Contrast Enhancement". Part I of this paper introduced a new automatic contrast enhancement technique: gray-level grouping (GLG). GLG is a general and powerful technique, which can be conveniently applied to a broad variety of low-contrast images and outperforms conventional contrast enhancement techniques. However, the basic GLG method still has limitations and cannot enhance certain classes of low-contrast images well, e.g., images with a noisy background. The basic GLG also cannot fulfill certain special application purposes, e.g., enhancing only part of an image which corresponds to a certain segment of the image histogram. In order to break through these limitations, this paper introduces an extension of the basic GLG algorithm, selective gray-level grouping (SGLG), which groups the histogram components in different segments of the grayscale using different criteria and, hence, is able to enhance different parts of the histogram to various extents. This paper also introduces two new preprocessing methods to eliminate background noise in noisy low-contrast images so that such images can be properly enhanced by the (S)GLG technique. The extension of (S)GLG to color images is also discussed in this paper. SGLG and its variations extend the capability of the basic GLG to a larger variety of low-contrast images, and can fulfill special application requirements. SGLG and its variations not only produce results superior to conventional contrast enhancement techniques, but are also fully automatic under most circumstances, and are applicable to a broad variety of images.     

Occurrence and removal of chloro-s-triazines in water treatment plants

Atrazine, simazine, and propazine and their major chlorinated degradates (deethylatrazine, deisopropylatrazine, and didealkylatrazine) are considered as a group to be endocrine-disrupting chemicals by the U.S. Environmental Protection Agency. On this basis, regulatory action levels are currently under consideration for the total chloro-s-triazine (TCT) levels in drinking waters. To assess the concentrations of each of these species in drinking water and their treatability in conventional water treatment, a comprehensive, full-scale studywas conducted that included frequent monitoring at 33 and 47 water utilities during 2003 and 2004, respectively. Approximately 900 paired raw and treated water samples were analyzed using a gas chromatography/mass spectrometry method with preconcentration using a mixed-mode, solid-phase extraction that allowed quantitation of each species including didealkylatrazine. The results showed that atrazine concentrations were generally well within the 3 microg/L maximum contaminant level (MCL) and that simazine and propazine concentrations were generally negligible. Ninety-fifth-percentile values for the ratio of TCT/atrazine were 4.8 and 4.7, respectively. Effectiveness of conventional treatment technologies, including carbon, was observed to vary significantly. Concerns that didealkyatrazine concentrations may be high and significantly elevate the TCT appear to be unfounded. In general, the results suggest that potential treatment requirements for TCT are not likely to be any more difficult for utilities to meet than the current requirements for atrazine.