Search results for "Mathematica"
showing 10 items of 7971 documents
Two-Sided Estimates of the Solution Set for the Reaction–Diffusion Problem with Uncertain Data
2009
We consider linear reaction–diffusion problems with mixed Dirichlet–Neumann–Robin conditions. The diffusion matrix, reaction coefficient, and the coefficient in the Robin boundary condition are defined with an uncertainty which allow bounded variations around some given mean values. A solution to such a problem cannot be exactly determined (it is a function in the set of “possible solutions” formed by generalized solutions related to possible data). The problem is to find parameters of this set. In this paper, we show that computable lower and upper bounds of the diameter (or radius) of the set can be expressed throughout problem data and parameters that regulate the indeterminacy range. Ou…
Review of Knowledge Management Models for Implementation within Advanced Product Quality Planning
2014
The purpose of this paper is to review different Knowledge Management Models (KMM) based on their strengths and weaknesses and to ascertain their possible implementation within the scope of the Advanced Product Quality Planning (APQP) procedure. The KMM listed are selected based on an extensive literature review. They are presented in a visual manner and analyzed based on their structure and features, versus a predetermined set of criteria. This study offers an overview and a critical discussion of the merits and faults of a number KMM and suggests possible improvement avenues.
Further Developments and Tests of a Progressive Algorithm for Multiple Criteria Decision Making
1993
P. Korhonen, H. Moskowitz, and J. Wallenius (1986) developed a progressive algorithm and the supporting theory for modeling and solving multiple criteria decision problems with discrete alternatives. A special feature of the algorithm is that it relaxes the usual assumption of a fixed set of available decision alternatives and complete knowledge of a decision maker's (DM's) preference structure or value function. The algorithm is based on progressively sampling the decision space, obtaining preference information from the DM, determining the likelihood of finding possibly/surely better alternatives, and based on this information, continuing the search or terminating it by making the final …
Construction and Implementation of LR(1) Parsers
1990
This chapter is devoted to the practical issues involved in the construction and use of deterministic LR(1) parsers. We shall show how the practical versions of LR (1) parsers, most notably the LALR (1) parsers, can be constructed efficiently, and we shall present methods for encoding LR(1) parsers as efficient RAM programs. Two versions of RAM program implementation are considered: in the first implementation the parsing program is table-driven, that is, the rules of the parser are encoded in a two-dimensional array which is simulated by a program body; in the other implementation the tabular information is further transformed into a set of program statements.
Detection and Isolation of Switches in Point Clouds of the German Railway Network
2015
In order to obtain an automated system of railway management, it is necessary to automatically detect, isolate and identify all switches in a point cloud which represents the railway. To realize this automated system of detection, a set of pre-processing steps is applied. The system begins by detecting and isolating tracks through application of a mask on each section of the point cloud. Then, it does a denoising through mathematical morphology and a compression in replacing a group of points by their centroid. Finally, it closes tracks holes through extrapolation. After that, the system does a low-level processing to search for all intersections between tracks, and records information on t…
PARAMETER BOUNDED ESTIMATION FOR QUASISPECIES MODELS OF MOLECULAR EVOLUTION
2006
Abstract The Quasispecies models identification for Evolutionary Dynamics is considered in a worst-case deterministic setting. These models analyze the DNA and RNA evolution or describe the population dynamics of viruses and bacteria. In this paper we identify the Fitness and the Replication Probability parameters of a genetic sequences, subject to a set of stringent constraints to have physical meaning and to guarantee positiveness. The conditional central estimate and the Uncertainty Intervals are determined. The effectiveness of the proposed procedure has been illustrated by means of simulation experiments while tests on real data are under concern.
Existence of a traveling wave solution in a free interface problem with fractional order kinetics
2021
Abstract In this paper we consider a system of two reaction-diffusion equations that models diffusional-thermal combustion with stepwise ignition-temperature kinetics and fractional reaction order 0 α 1 . We turn the free interface problem into a scalar free boundary problem coupled with an integral equation. The main intermediary step is to reduce the scalar problem to the study of a non-Lipschitz vector field in dimension 2. The latter is treated by qualitative topological methods based on the Poincare-Bendixson Theorem. The phase portrait is determined and the existence of a stable manifold at the origin is proved. A significant result is that the settling time to reach the origin is fin…
Universal freezing of quantum correlations within the geometric approach
2015
Quantum correlations in a composite system can be measured by resorting to a geometric approach, according to which the distance from the state of the system to a suitable set of classically correlated states is considered. Here we show that all distance functions, which respect natural assumptions of invariance under transposition, convexity, and contractivity under quantum channels, give rise to geometric quantifiers of quantum correlations which exhibit the peculiar freezing phenomenon, i.e., remain constant during the evolution of a paradigmatic class of states of two qubits each independently interacting with a non-dissipative decohering environment. Our results demonstrate from first …
Role of the colored noise in a FitzHugh-Nagumo system driven by a periodic signal
2007
During these last years the interest in neuronal dynamics increased. The study of this kind of system has been carried out by using the FitzHugh-Nagumo (FHN) model that is a simplified modification of the Hodgkin-Huxley model. Many interesting phenomena can be observed in the presence of fluctuations: modification of detection threshold by manipulation of noisy parameters (FHN model), noise-induced activation and coeherence resonance for suitable noise amplitude (absence of periodic signal), resonant activation for high periodic signals and noise reduction, intrinsic stochastic resonance (ISR) in Hodgkin-Huxley neuron and the enhancement of a weak signal by tuning the subthreshold intrinsic…
Global sensitivity analysis for micropollutant modeling by means of an urban integrated approach
2015
The paper presents the sensitivity analysis of an integrated urban water quality system by means of the global sensitivity analysis (GSA). Specifically, an home-made integrated model developed in previous studies has been modified in order to include the micropollutant assessment (namely, sulfamethoxazole - SMX). The model is able to estimate also the interactions between the three components of the system: sewer system (SS), wastewater treatment plant (WWTP) and the receiving water body (RWB). The analysis has been applied to an experimental catchment nearby Palermo (Italy): the Nocella catchment. Five scenarios each characterized by different combinations of sub-systems (i.e., SS, WWTP an…