Search results for "computer.software_genre"

Learning Temporal Regularities of User Behavior for Anomaly Detection

2001

Fast expansion of inexpensive computers and computer networks has dramatically increased number of computer security incidents during last years. While quite many computer systems are still vulnerable to numerous attacks, intrusion detection has become vitally important as a response to constantly increasing number of threats. In this paper we discuss an approach to discover temporal and sequential regularities in user behavior. We present an algorithm that allows creating and maintaining user profiles relying not only on sequential information but taking into account temporal features, such as events' lengths and possible temporal relations between them. The constructed profiles represent …

An fMRI Study to Analyze Neural Correlates of Presence during Virtual Reality Experiences

2013

[EN] In the field of virtual reality (VR), many efforts have been made to analyze presence, the sense of being in the virtual world. However, it is only recently that functional magnetic resonance imaging (fMRI) has been used to study presence during an automatic navigation through a virtual environment. In the present work, our aim was to use fMRI to study the sense of presence during a VR-free navigation task, in comparison with visualization of photographs and videos (automatic navigations through the same environment). The main goal was to analyze the usefulness of fMRI for this purpose, evaluating whether, in this context, the interaction between the subject and the environment is perf…

Analysis and simulation of creativity learning by means of artificial neural networks

2007

The paper presents a new neural network approach for analysis and simulation of creative behavior. The used concept of Dynamically Controlled Neural Gas (DyCoNG) entails a combination of Dynamically Controlled Network [Perl, J. (2004a). A neural network approach to movement pattern analysis. Human Movement Science,23, 605-620] and Growing Neural Gas (Fritzke, 1995) by quality neurons. A quality neuron reflects the rareness of a piece of information and therefore can measure the originality of a recorded activity that was assigned to the neuron during the network training. The DyCoNG approach was validated using data from a longitudinal field-based study. The creative behavior of 42 particip…

Clustering Bacteria Species Using Neural Gas: Preliminary Study

2009

In this work a method for clustering and visualization of bacteria taxonomy is presented. A modified version of the Batch Median Neural Gas (BNG) algorithm is proposed. The BNG algorithm is able to manage non vectorial data given as a dissimilarity matrix. We tested the modified BNG on the dissimilarity matrix obtained from sequences alignment and computing distances using bacteria genotype information regarding the16S rRNA housekeeping gene, which represents a stable part of bacteria genome. The dataset used for the experiments is obtained from the Ribosomal Database Project II, and it is made of 5159 sequences of 16S rRNA genes. Preliminary results of the experiments show a promising abil…

Functional relevance and diagnostic utility of ROI-based and voxel-based diffusion-tensor imaging analyses in mild cognitive impairment

2007

Psychophysically Tuned Divisive Normalization Approximately Factorizes the PDF of Natural Images

2010

The conventional approach in computational neuroscience in favor of the efficient coding hypothesis goes from image statistics to perception. It has been argued that the behavior of the early stages of biological visual processing (e.g., spatial frequency analyzers and their nonlinearities) may be obtained from image samples and the efficient coding hypothesis using no psychophysical or physiological information. In this work we address the same issue in the opposite direction: from perception to image statistics. We show that psychophysically fitted image representation in V1 has appealing statistical properties, for example, approximate PDF factorization and substantial mutual informatio…

Cycle-triggered averaging of respiration-related neuronal activity

1985

Abstract A computer system is presented which provides off-line computation of cycle-triggered histograms (CTH) of respiration-related neuronal activity. Binwidths of the histograms are freely selectable by software from 10 ms to 100 ms. For special evaluation purposes. CTHs can be standardized in different ways concerning cycle duration as well as amplitude. Time incidence of maximum frequency, center of gravity and expiration-to-inspiration phase transition within the respiratory cycle are computed. The system employs special hardware interfaces to an 8-bit microcomputer which are briefly described. Data acquisition, data manipulation and output handling of the results are performed by ch…

2021

Aging and diabetes lead to protein glycation and cause dysfunction of collagen-containing tissues. The accompanying structural and functional changes of collagen significantly contribute to the development of various pathological malformations affecting the skin, blood vessels, and nerves, causing a number of complications, increasing disability risks and threat to life. In fact, no methods of non-invasive assessment of glycation and associated metabolic processes in biotissues or prediction of possible skin complications, e.g., ulcers, currently exist for endocrinologists and clinical diagnosis. In this publication, utilizing emerging photonics-based technology, innovative solutions in mac…

SymbioGenomesDB: a database for the integration and access to knowledge on host-symbiont relationships.

2014

Symbiotic relationships occur naturally throughout the tree of life, either in a commensal, mutualistic or pathogenic manner. The genomes of multiple organisms involved in symbiosis are rapidly being sequenced and becoming available, especially those from the microbial world. Currently, there are numerous databases that offer information on specific organisms or models, but none offer a global understanding on relationships between organisms, their interactions and capabilities within their niche, as well as their role as part of a system, in this case, their role in symbiosis. We have developed the SymbioGenomesDB as a community database resource for laboratories which intend to investigat…

Analysis of data fusion techniques for multi-microphone audio event detection in adverse environments

2017

Acoustic event detection (AED) is currently a very active research area with multiple applications in the development of smart acoustic spaces. In this context, the advances brought by Internet of Things (IoT) platforms where multiple distributed microphones are available have also contributed to this interest. In such scenarios, the use of data fusion techniques merging information from several sensors becomes an important aspect in the design of multi-microphone AED systems. In this paper, we present a preliminary analysis of several data-fusion techniques aimed at improving the recognition accuracy of an AED system by taking advantage of the diversity provided by multiple microphones in …