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This paper addresses the need for a semantic video-object approach for efficient storage and manipulation of video data to respond to the needs of several classes of potential applications when efficient management and deductions over voluminous data are involved. We present the VIGILANT conceptual model for content and event-based retrieval of video images and clips using automatic annotation and...
Easy access to the World Wide Web has raised concerns about copyright issues and plagiarism. It is easy to copy someone else’s work and submit it as someone’s own. This problem has been targeted by many systems, which use very similar approaches. These approaches are compared in this paper and suggestions are made when different strategies are more applicable than others. Some alternative approaches...
Previous works in Information Retrieval show that using pieces of text obtain better results than using the whole document as the basic unit to compare with the user’s query. This kind of IR systems is usually called Passage Retrieval (PR). This paper discusses the use of our PR system in the question answering process (QA). Our main objective is to examine if a PR system provide a better support...
EnterTheGrid is the largest independent Grid portal in existence. It has been build entirely on XML-technology, from the database up to the user interface. In this paper we describe several XML design patterns, that were developed for the site. A hybrid XML data model is used as the basis to describe the items of the site. A search engine is developed using XSLT/XPath and it is describer how information...
We introduce a proposal to theoretically characterize Information Retrieval (IR) supporting metadata. The proposed model has its foundation in a classical approach to IR, namely vector models. These models are simple and implementations are fast, their term-weighting approach improve retrieval performance, allow partial matching, and support document ranking. The proposed characterization includes...
A three-dimensional model of diffusion limited coral growth is introduced. As opposed to previous models, in this model we take a “polyp oriented” approach. Here, coral morphogenesis is the result of the collective behaviour of the individual coral polyps. In the polyp oriented model, branching occurs spontaneously, as opposed to previous models in which an explicit rule was responsible for branching...
We present a new approach to modelling of foraminiferal shells. Previous models referred to fixed reference axes and neglected apertures, which play a crucial role in morphogenesis of shells. Our 2D preliminary model applies the moving reference system based on introducing of apertures and minimization of the local communication path (LCP). LCP defines the position of every final aperture. A formal...
The present work outlines the results of the Parallel Discrete Event Simulation (PDES) utilization for solving an individual based model: Fish Schools. This type of model cannot be solved through analytical methods, thus simulation techniques are necessary. The greater problem presented by this type of model is the high computing capacity necessary for solving middle-high size problems (hundreds to...
The ecology of the human intestinal microflora and its interaction with the host are poorly understood. Though more and more data are being acquired, in part using modern molecular methods, development of a quantitative theory has not kept pace with this development. This is in part due to the complexity of the system, and to the lack of simulation environments in which to test what the ecological...
In recent years, the study of immune response behaviour through mathematical and computational models has been the focus of considerable efforts. We propose a mesoscopic model to combine the most useful features of the microscopic and macroscopic approaches, which have been the alternatives to date. Cellular automata and Monte Carlo simulation are used to describe the humoral and T-cell mediated immune...
A new method is proposed to select the binary n-tuples of 0s and 1s by decreasing order of there occurrence probabilities in stochastic Boolean models. This method can be applied to evaluate fault trees in Reliability Engineering and Risk Analysis, as well as to many other problems described by a stochastic Boolean structure. The selecting criterion is exclusively based on the positions of 0s and...
In this paper we propose the use of Support Vector Machine (SVM) to evaluate system reliability. The main idea is to develop an estimation algorithm by training a SVM on a restricted data set, replacing the system performance model evaluation by a simpler calculation. The proposed approach is illustrated by an example. System reliability is properly emulated by training a SVM with a small amount of...
Agent-based paradigm is increasingly applied to building computing systems where conventionally latent requirements, e.g. time-sensitivity of data and event validity, and/or truth-values of predicates, timeliness of communication, and others become essential for correct functioning of systems. In many such cases empirical demonstration of expected behaviour is not sufficient, formal verification of...
In this paper, we present a method for generating very expressiv e decision trees over a functional logic language. The generation of the tree folio ws a short-to-long search which is guided by the MDL principle. Once a solution is found, the construction of the tree goes on in order to obtain more solutions ordered as well by description length. The result is a multi-tree which is populated taking...
We present here a performance model which simulates different versions of the hierarchical treecode on different computer architectures, including hybrid architectures, where a parallel distributed general purpose host is connected to special purpose devices that accelerate specific compute-intense tasks. We focus on the inverse square force computation task, and study the interaction of the treecode...
In this article we analyse computational processes and investigate characteristics of iterative stochastic algorithms for control and identification based on the auxiliary performance index (API) approach. A workable API is the one which (1) depends on available values only, (2) has the same domain as the original performance index (OPI) has, and (3) achieves its minimum at the same point in the domain...
This paper deals with computations of sensitivity indices in global sensitivity analysis. Given a model y=f( x1,...,xk, where the k input factors xi’s are uncorrelated with one another, one can see y as the realisation of a stochastic process obtained by sampling each of the xi’s from its marginal distribution. The sensitivity indices are related to the decomposition of the variance...
One approach how to solve a linear optimization is based on interior point method. This method requires the solution of large linear system equations. A special matrix factorization techniques that exploit the structure of the constraint matrix has been suggested for its computation. The method of Birge and Qi has been reported as efficient, stable and accurate for two-stage stochastic programs. In...
Metocean data fields (atmospheric pressure, wind speed, sea surface and air temperature, sea waves etc.) are multivariate and multidimensional, i.e. have a complex spatial and temporal variability. Only 10–20 years back the environmental databases wholly consisted of the time series (ship observation, sea and coastal monitoring stations, automatic probes and buoys, satellites) in fixed points of spatial...
In the paper is presented an approach to simulation of gender interaction in artificial society. We are studying the process of the male’s and female’s interaction based on subject-object relations. On the one hand, the females radiate the charm pulses. Responding to these pulses, the males choose a female. On the other hand, the males accumulate a resource and females choose a male, having the maximum...
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