Search results for "Hardware and Architecture"
showing 10 items of 556 documents
Bio-inspired security analysis for IoT scenarios
2020
Computer security has recently become more and more important as the world economy dependency from data has kept growing. The complexity of the systems that need to be kept secure calls for new models capable of abstracting the interdependencies among heterogeneous components that cooperate at providing the desired service. A promising approach is attack graph analysis, however, the manual analysis of attack graphs is tedious and error prone. In this paper we propose to apply the metabolic network model to attack graph analysis, using three interacting bio-inspired algorithms: topological analysis, flux balance analysis, and extreme pathway analysis. A developed framework for graph building…
BED: A new dataset for EEG-based biometrics
2021
Various recent research works have focused on the use of electroencephalography (EEG) signals in the field of biometrics. However, advances in this area have somehow been limited by the absence of a common testbed that would make it possible to easily compare the performance of different proposals. In this work, we present a data set that has been specifically designed to allow researchers to attempt new biometric approaches that use EEG signals captured by using relatively inexpensive consumer-grade devices. The proposed data set has been made publicly accessible and can be downloaded from https://doi.org/10.5281/zenodo.4309471 . It contains EEG recordings and responses from 21 individuals…
Brightness and contrast do not affect visually induced motion sickness in a passively-flown fixed-base flight simulator
2016
Abstract Background Visually Induced Motion Sickness (VIMS) or simulator sickness is often elicited by a visual stimulus that lacks the appropriate vestibular or proprioceptive feedback. In this study, we chose to investigate the effects of brightness and contrast of the visual scene on VIMS. Hypothesis We hypothesized that visual environments differing in brightness or contrast would differentially induce VIMS. The symptoms of VIMS should be most severe for the combination of high brightness and high contrast and conversely lowest for the low brightness and low contrast condition. Methods 33 healthy subjects were tested in a fixed-base flight simulator. Each subject flew in four consecutiv…
A COMPARATIVE STUDY BETWEEN ´ BIHARMONIC BEZIER SURFACES AND BIHARMONIC EXTREMAL SURFACES
2009
AbstractGiven a prescribed boundary of a Bezier surface, we compare the Bezier surfaces generated by two different methods, i.e., the Bezier surface minimising the biharmonic functional and the unique Bezier surface solution of the biharmonic equation with prescribed boundary. Although often the two types of surfaces look visually the same, we show that they are indeed different. In this paper, we provide a theoretical argument showing why the two types of surfaces are not always the same.
Exploiting seeding of random number generators for efficient domain decomposition parallelization of dissipative particle dynamics
2013
Abstract Dissipative particle dynamics (DPD) is a new promising method commonly used in coarse-grained simulations of soft matter and biomolecular systems at constant temperature. The DPD thermostat involves the evaluation of stochastic or random forces between pairs of neighboring particles in every time step. In a parallel computing environment, the transfer of these forces from node to node can be very time consuming. In this paper we describe the implementation of a seeded random number generator with three input seeds at each step which enables the complete generation of the pairwise stochastic forces in parallel DPD simulations with minimal communication between nodes.
Fitbit for learning: Towards capturing the learning experience using wearable sensing
2020
The assessment of learning during class activities mostly relies on standardized questionnaires to evaluate the efficacy of the learning design elements. However, standardized questionnaires pose additional strain on students, do not provide “temporal” information during the learning experience, require considerable effort and language competence, and sometimes are not appropriate. To overcome these challenges, we propose using wearable devices, which allow for continuous and unobtrusive monitoring of physiological parameters during learning. In this paper we set out to quantify how well we can infer students’ learning experience from wrist-worn devices capturing physiological data. We coll…
A family of experiments to generate graphical user interfaces from BPMN models with stereotypes
2021
Abstract Context: A significant gap separates Business Process Model and Notation (BPMN) models representing processes from the design of Graphical User Interfaces (GUIs). Objective: This paper reports on a family of experiments to validate a method to automatically generate GUIs from BPMN models using stereotypes complemented with UML class primitives, and transformation rules. Method: We conducted two replications (23 and 31 subjects respectively) in which we compared two methods to generate GUIs from BPMN models; one automatic (using Stereotyped BPMN models) and one manual (using Non-stereotyped BPMN models). The study focuses on comparing effort, accuracy, and satisfaction (in terms of …
Noise-tolerant efficient inductive synthesis of regular expressions from good examples
1997
We present an almost linear time method of inductive synthesis restoring simple regular expressions from one representative (good) example. In particular, we consider synthesis of expressions of star-height one, where we allow one union operation under each iteration, and synthesis of expressions without union operations from examples that may contain mistakes. In both cases we provide sufficient conditions defining precisely the class of target expressions and the notion of good examples under which the synthesis algorithm works correctly, and present the proof of correctness. In the case of expressions with unions the proof is based on novel results in the combinatorics of words. A genera…
Model approximation for two-dimensional Markovian jump systems with state-delays and imperfect mode information
2014
Published version of an article in the journal: Multidimensional Systems and Signal Processing. Also available from the publisher at: http://dx.doi.org/10.1007/s11045-013-0276-x This paper is concerned with the problem of {Mathematical expression} model approximation for a class of two-dimensional (2-D) discrete-time Markovian jump linear systems with state-delays and imperfect mode information. The 2-D system is described by the well-known Fornasini-Marchesini local state-space model, and the imperfect mode information in the Markov chain simultaneously involves the exactly known, partially unknown and uncertain transition probabilities. By using the characteristics of the transition proba…
On the chromatic number of disk graphs
1998
Colorings of disk graphs arise in the study of the frequency-assignment problem in broadcast networks. Motivated by the observations that the chromatic number of graphs modeling real networks hardly exceeds their clique number, we examine the related properties of the unit disk (UD) graphs and their different generalizations. For all these graphs including the most general class of the double disk (DD) graphs, it is shown that X(G) ≤ c.ω(G) for a constant c. Several coloring algorithms are analyzed for disk graphs, aiming to improve the bounds on X(G). We find that their worst-case performance expressed in the number of used colors is indeed reached in some instances.