Search results for "Artificial"
showing 10 items of 7394 documents
An algorithm for earthquakes clustering based on maximum likelihood
2007
In this paper we propose a clustering technique set up to separate and find out the two main components of seismicity: the background seismicity and the triggered one. We suppose that a seismic catalogue is the realization of a non homogeneous space-time Poisson clustered process, with a different parametrization for the intensity function of the Poisson-type component and of the clustered (triggered) component. The method here proposed assigns each earthquake to the cluster of earthquakes, or to the set of independent events, according to the increment to the likelihood function, computed using the conditional intensity function estimated by maximum likelihood methods and iteratively chang…
Combining similarity measures in content-based image retrieval
2008
The purpose of content based image retrieval (CBIR) systems is to allow users to retrieve pictures from large image repositories. In a CBIR system, an image is usually represented as a set of low level descriptors from which a series of underlying similarity or distance functions are used to conveniently drive the different types of queries. Recent work deals with combination of distances or scores from different and usually independent representations in an attempt to induce high level semantics from the low level descriptors of the images. Choosing the best method to combine these results requires a careful analysis and, in most cases, the use of ad-hoc strategies. Combination based on or…
Semi-Supervised Remote Sensing Image Classification based on Clustering and the Mean Map Kernel
2008
This paper presents a semi-supervised classifier based on the combination of the expectation-maximization (EM) algorithm for Gaussian mixture models (GMM) and the mean map kernel. The proposed method uses the most reliable samples in terms of maximum likelihood to compute a kernel function that accurately reflects the similarity between clusters in the kernel space. The proposed method improves classification accuracy in situations where the available labeled information does not properly describe the classes in the test image.
Optical flow estimation from multichannel spherical image decomposition
2011
The problem of optical flow estimation is largely discussed in computer vision domain for perspective images. It was also proven that, in terms of optical flow analysis from these images, we have difficulty distinguishing between some motion fields obtained with little camera motion. The omnidirectional cameras provided images with large filed of view. These images contain global information about motion and allow to remove the ambiguity present in perspective case. Nevertheless, these images contain significant radial distortions that is necessary to take into account when treating these images to estimate the motion. In this paper, we shall describe new way to compute efficient optical fl…
Restricted Neighborhood Search Clustering Revisited: An Evolutionary Computation Perspective
2013
Protein-protein interaction networks have been broadly studied in the last few years, in order to understand the behavior of proteins inside the cell. Proteins interacting with each other often share common biological functions or they participate in the same biological process. Thus, discovering protein complexes made of groups of proteins strictly related, can be useful to predict protein functions. Clustering techniques have been widely employed to detect significative biological complexes. In this paper, we integrate one of the most popular network clustering techniques, namely the Restricted Neighborhood Search Clustering (RNSC), with evolutionary computation. The two cost functions in…
Employing fuzzy logic in the diagnosis of a clinical case
2010
Fuzzy logic is a logical calculus which operates with many truth values (while classical logic works with the two values of true and false). Since fuzzy logic considers the truth of scientific statements like something softened, it is fruitfully applied to the study of biological phenomena, biology is indeed considered the field of complexity, uncertainty and vagueness. In this paper fuzzy logic is successfully applied to the clinical diagnosis of a patient who suffers from different diseases bound by a complex causal chain. In this work it is presented a mathematical foundation of fuzzy logic (with connectives and inference rules) and then the application of fuzzy reasoning to the study of…
Estimation of Electrical Pathways Finding Minimal Cost Paths from Electro-Anatomical Mapping of the Left Ventricle
2014
The electrical activation of the heart is a complex physiological process that is essential for the understanding of several cardiac dysfunctions, such as ventricular tachycardia VT. Nowadays, electro-anatomical mappings of patient-specific activation times on the left ventricle surface can be estimated, providing crucial information to the clinicians for guiding cardiac treatment. However, some electrical pathways of particular interest such as Purkinje or still viable conduction channels are difficult to interpret in these maps. We present here a novel method to find some of these electrical pathways using minimal cost paths computations on surface maps. Experiments to validate the propos…
Industrial Areas and the City. Equalization and Compensation in a Value-Oriented Allocation Pattern
2016
This study deals with the allocation of the firms in a large industrial area of Quarto, a town in the Naples’ district subject to a “Piano di Insediamenti Industriali” – PIP (Industrial Settlement Masterplan). The main concern of the Municipality is the fair integration between environmental issues, economic development and urban identity. Therefore a structured evaluation process, based on a survey about the company profiles and their geographical location, has been carried out in order to make the plan meet the needs of the firms, and to select the best companies to settle in the planned area. A “generative” MAVT pattern has been designed to outline several layout options and to select th…
Miejsce międzypokoleniowego uczenia się w procesie hominizacji
2016
This article presents the results of a pilot and exploration study. The main objective of the research was to investigate the differences of intergenerational learning in the process of hominisation. For the purpose of the study the author used the quantitative strategy of research and author’s instrument of measurement. In the study participated 50 adult respondents from province opolskie. The research in question combines in a way such fields of knowledge as anthropology, pedagogics and psychology; the aim of the combination is to explore the processes which support the development of a human being in light of andragogy. Two conceptions have constituted the theoretical and methodological …
Activities with Educational Robotics: Research Model and Tools for Evaluation of Progress
2019
The use of robots in the learning process has been popular since S. Papert developed his LOGO Turtle idea and argued that students can construct their own knowledge, test their constructive solutions and be motivated to learn if they use robotics in the learning process. Today, the idea of using elements of robotics in the learning process is no longer new and innovative but there are still elements that can be developed and issues that should be discussed. In this chapter, the authors provide the research model and five research tools (structured observation protocol, evaluation of the possible risks of early school leaving to be filled in by teachers before and after activities, students’…