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Parametric representation for curves is important in computer-aided geometric design, medical imaging, computer vision, computer graphics, shape matching, and face/object recognition. They are far better alternatives to free form representation, which are plagued with unboundedness and stability problems. This paper deals with the problem of fitting approximating B-spline curves with high compression...
An automated recognition technique was proposed for providing information on such as the skeleton of thoracic aorta, diameter of each cross-section along the skeleton, curvature of it and position of the aneurysm on the aorta using multi-slice CT images. The information was indispensable to design a stent with perfect fitting to the patient's aorta aneurysm region so that the stent kept the original...
Photonic cluster states are fabricated within the internal structure of a multimode frequency comb. Projective measurements combined with ultrafast pulse shaping allow the creation of arbitrary cluster states with no change in the optical footprint.
To analyze the characteristics of the blood vessels quantitatively is of great importance to the diagnosis of different diseases, e.g., stenosis, diabetic retinopathy, tumor and so on. However, the occurrence of imaging noise or illumination variation may include difficulty for image analysis, especially for accurate quantitative analysis. Therefore, more efficient algorithms for vessel image thresholding,...
Many real time applications, they are generated continues flow of data streams have became more popular now a days. Therefore many researches attracted clustering data streams. Most of data stream clustering algorithms based on distance function which find out clusters with spiracle of shape clusters and unable to deal noisy data. Therefore density based clustering algorithms substitute remarkable...
Several clustering algorithms have been extensively used to analyze vast amounts of spatial data. One of these algorithms is the SNN (Shared Nearest Neighbor), a density-based algorithm, which has several advantages when analyzing this type of data due to its ability of identifying clusters of different shapes, sizes and densities, as well as the capability to deal with noise. Having into account...
Density-based clustering can detect arbitrary shape clusters, handle outliers and do not need the number of clusters in advance. However, they cannot work properly in multi density environments. The existing multi density clustering algorithms have some problems in order to be applicable for data streams such as the need of whole data to perform clustering, two-pass clustering and high execution time...
We propose an improved randomized circle detection method. The improved method reduces the computational complexity of the randomized circle detection method by a factor of two. We then apply the proposed method to detection of circular traffic signs. For traffic images taken in complex scenarios, the colors of interest are first segmented, obtaining potential regions of traffic signs. By applying...
In this paper, we propose a new shape decomposition method based on visual perception for shape matching and retrieval which uses the protrusive corners under multiple scales. Our approach composes of a multi-scale shape decomposition procedure and a contour segments matching procedure. Firstly, morphological operations are used for more stable and visual perceptual corners to get the contour segmented...
In this work, the noise generation problem due to the implementation of porous baffles as weather protection barriers on offshore oil and gas platforms is investigated. Attention is focused on the design of the experiment. A cognitive process is implemented to identify the major parameters instigating noise generation on these structures. A cognitive approach is also implemented to analyse the noise...
A shape signature is defined as any 1-D function on a shape, which is a compact and concise representation for some essence of the shape. Although a variety of shape signatures are proposed and utilized in shape retrieval and recognition tasks, the existing signatures cannot yet provide entirely satisfactory solutions to describe the shape variations well, especially when significant noise or articulation...
We present an automatic method for fitting multiple B-spline curves to unorganized planar points. The method works on point clouds which have complicated topological structures and a single curve is insufficient for fitting the shape. A divide-and-merge algorithm is developed for dividing the unorganized data points into several groups while each group represents a smooth curve. Each point group is...
Photo-identification of dolphin individuals is a commonly used technique in ecological sciences to monitor state and health of individuals, as well as to study the social structure and distribution of a population. Uniqueness of some forms of damage sustained by the trailing edge of the dorsal fin throughout an individual's life allows it to be used to identify the individual. Traditional photo-identification...
Bio-kinematic characterisations of human exercises constitute dealing with parameters such as velocity, acceleration, joint angles, etc. A majority of these are measured directly from various sensors ranging from RGB cameras to inertial sensors. However, due to certain limitations associated with these sensors, such as inherent noise, filters are required to be implemented to subjugate the effect...
Current bio-kinematic encoders use velocity, acceleration and angular information to encode human exercises. However, in exercise physiology there is a need to distinguish between the shape of the trajectory and its execution dynamics. In this paper we propose such a two-component model and explore how best to compute these components of an action. In particular, we show how a new spatial indexing...
In this contribution, we present a configurable digital emulator of pulses which generates analog signals with fully programmable shape, energy and temporal distributions. Two independent channels, which can be related in terms of the instants of occurrence of the events, allow generation of pulses with programmable delay with resolution below 12 ps. The instrument also combines the advantage of being...
In this paper, the authors proposed a Hybrid PD (AE) sensor which could tell us an absolute distance from PD source. The proposed sensor installed at one fixed position of power transformer tank wall could detect HF signal and ultrasonic one simultaneously. Ignoring faster arrival time of HF signal, an approximated absolute distance from PD source could be derived easily. Moreover, applying time series...
Image matching based on contour is an important issue in computer vision, navigation and pattern recognition. The image matching methods like curvature-based methods and corner-based methods have poor robustness to the contour's noise and distortion, and some matching methods are applied only to closed contours. A novel contour representation and matching algorithm, based on local curvature scale,...
The issue of near duplicate document image retrieval is addressed in this paper, which is characterized by not only encoding each individual word in the image but also modeling its local spatial configuration. On representing each word in the image as a string in terms of its shape characteristics, a lexicon is first learnt from a training set. Then a word in an arbitrary document image can be soft...
This article presents a method for generating semi-synthetic images of old documents where the pages might be torn (not flat). By using only 2D deformation models, most existing methods give non-realistic synthetic document images. Thus, we propose to use 3D approach for reproducing geometric distortions in real documents. First, a new proposed texture coordinate generation technique extracts texture...
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