Kernel Bandwidth Estimation for Nonparametric Modeling

Kernel density estimation is a nonparametric procedure for probability density modeling, which has found several applications in various fields. The smoothness and modeling ability of the functional approximation are controlled by the kernel bandwidth. In this paper, we describe a Bayesian estimation method for finding the bandwidth from a given data set. The proposed bandwidth estimation method is applied in three different computational-intelligence methods that rely on kernel density estimation: 1) scale space; 2) mean shift; and 3) quantum clustering. The third method is a novel approach that relies on the principles of quantum mechanics. This method is based on the analogy between data samples and quantum particles and uses the Schrodinger potential as a cost function. The proposed methodology is used for blind-source separation of modulated signals and for terrain segmentation based on topography information.     

On the existence of an optimal solution of the Mayer problem governed by 2D continuous counterpart of the Fornasini-Marchesini model

In the paper the optimization problem described by some nonlinear hyperbolic equation being continuous counterpart of the Fornasini-Marchesini model is considered. A theorem on the existence of at least one solution to this hyperbolic PDE is proved and some properties of the set of all solutions are established. The existence of a solution to an optimization problem under appropriate assumptions is the main result of this paper. Some application of the obtained results to the process of gas filtration is also presented.     

Immunological effects of an arginine side chain contaminating synthetically prepared peptides

We examined the effect of a nitric oxide (NO) quencher, stroma-free human hemoglobin A (HbA0; 0.01, 0.05, 0.1, 0.2 g/kg), on the blood flow measured using the Doppler flow technique, tumor oxygen pressure (pO2) and the diameter of the arterioles using R3230Ac mammary adenocarcinoma as the tumor model. In female Fischer 344 rats with 1-cm-diameter tumors implanted in the lateral aspect of the left quadriceps, intravenous infusion of 0.1 and 0.2 g/kg HbA0 decreased both central tumor and peripheral tumor blood flow by 20-30% (P < 0.05). Tumor pO2 decreased 28% with 0.2 g/kg HbA0, from 15 mm Hg (baseline) to 11 mm Hg at 10 min (P = 0.02). Although 0.2 g/kg HbA0 increased blood flow 55% in the left quadriceps muscle proximal to the implanted tumor (P < 0.05), HbA0 had little effect on blood flow in right quadriceps muscle with no tumor implanted, and increased right quadriceps pO2, from 21 mm Hg (baseline) to 23 mm Hg at 10 min (P = 0.03). HbA0 increased mean arterial pressure 5-10% in a manner that was dependent on dose while heart rate concurrently decreased 9-19%. The diameter of the arterioles supplying the tumor was rapidly reduced 10% by 0.2 g/kg HbA0 (P = 0.037) and remained stable through 60 min of observation (P = 0.005). HbA0 selectively reduces tumor blood flow and tumor pO2 through vasoconstriction of the arterioles supplying the tumor. Vascular NO quenching provides an alternative to NO synthase inhibition as a means to achieve the goal of selective tumor hypoxia.     

Spatial mapping, working memory, and the fimbria–fornix system.

13 Long-Evans male hooded rats with lesions severing either the subcallosal fornix (Fo) or the medial half of the fimbria (Fi) were compared with 9 control (Co) and sham-operated Ss in a working memory task (serial alternation) and a reference memory task (cue-guided alternation). Neither task required spatial mapping strategy. Findings indicate that damaging the Fi, but not the Fo, caused a severe deficit in the serial alternation task. Analysis of individual performance revealed that Fi Ss either adopted a "side strategy," resulting in chance performance, or actively repeated previous successful choices, resulting in worse than chance performance. This active perseveration required an intact working-memory mechanism. In the cue-guided alternation task, Fo Ss proved superior to Co and Fi Ss. Findings are inconsistent with notions that the exclusive role of the hippocampus is spatial mapping or storing of recent memories, and indicate differential involvement of the fimbria and fornix fibers in behavior. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Elevated-temperature deformation properties of a HfC modified Ti-48Al-2Mn-2Nb matrix particulate composite

Rapid solidification techniques in combination with HIPing have been used to produce Ti-48Al-2Mn-2Nb and a Ti-48Al-2Mn-2Nb+15 wt% HfC composite. While the composite does contain several second phases within the + ₂ matrix, none was identified to be HfC. The elevated-temperature properties were determined by constant velocity compression and constant load tensile testing in air between 1000 and 1173 K. Such testing indicated that the elevated temperature strengths of the HfC-modified aluminide was superior to those of the unreinforced matrix with the best 1100 K temperature slow strain rate properties for both materials being achieved after high-temperature annealing prior to testing. Examination of the microstructures after deformation in combination with the measured stress exponents and activation energies suggest that creep resistance of the HfC-modified form is due to solid-solution strengthening from carbon and hafnium rather than the presence of second phases.     

Application of 2D systems to investigation of a process of gas filtration

In the paper, a process of gas filtration described by the 2D system with controls is considered. Sufficient conditions for the existence of optimal process are proved.     

Prediction and tracking of moving objects in image sequences

We employ a prediction model for moving object velocity and location estimation derived from Bayesian theory. The optical flow of a certain moving object depends on the history of its previous values. A joint optical flow estimation and moving object segmentation algorithm is used for the initialization of the tracking algorithm. The segmentation of the moving objects is determined by appropriately classifying the unlabeled and the occluding regions. Segmentation and optical flow tracking is used for predicting future frames.     

Watermarking mesh-based representations of 3-D objects using local moments.

A new methodology for fingerprinting and watermarking three-dimensional (3-D) graphical objects is proposed in this paper. The 3-D graphical objects are described by means of polygonal meshes. The information to be embedded is provided as a binary code. A watermarking methodology has two stages: embedding and detecting the information that has been embedded in the given media. The information is embedded by means of local geometrical perturbations while maintaining the local connectivity. A neighborhood localized measure is used for selecting appropriate vertices for watermarking. A study is undertaken in order to verify the suitability of this measure for selecting vertices from regions where geometrical perturbations are less perceptible. Two different watermarking algorithms, that do not require the original 3-D graphical object in the detection stage, are proposed. The two algorithms differ with respect to the type of constraint to be embedded in the local structure: by using parallel planes and bounding ellipsoids, respectively. The information capacity of various 3-D meshes is analyzed when using the proposed 3-D watermarking algorithms. The robustness of the 3-D watermarking algorithms is tested to noise perturbation and to object cropping.     

Is the nature-nuture debate on the verge of extinction?

Presents 4 arguments in opposition to the position that the nature–nurture debate is no longer as contentious as it once was. First, the nature–nurture controversy, conceived of as an attempt to assign relative weightings of importance to genotype and environment in relation to psychological phenomena, is no closer to being settled today than it was at any point in the past. Second, though of considerable consequence for psychological theory and practice, the mapping of the human genome will not assist in the settlement of the nature–nurture debate. Third, heritability studies are of little value to psychologists and cannot help in the resolution of the debate. Fourth, the nature–nurture controversy is not a scientific issue. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)