Search results for "Minification"
showing 10 items of 91 documents
Heuristics and meta-heuristics for 2-layer straight line crossing minimization
2003
AbstractThis paper presents extensive computational experiments to compare 12 heuristics and 2 meta-heuristics for the problem of minimizing straight-line crossings in a 2-layer graph. These experiments show that the performance of the heuristics (largely based on simple ordering rules) drastically deteriorates as the graphs become sparser. A tabu search metaheuristic yields the best results for relatively dense graphs, with a GRASP implementation as close second. Furthermore, the GRASP approach outperforms all other approaches when tackling low-density graphs.
Differential Leakage Factor in Electrical Machines Equipped with Asymmetrical Multiphase Windings: a General Investigation
2019
This paper presents an investigation in terms of degree of unbalance and leakage factor of electrical machines equipped with multiphase windings. The analysis has been carried out through 4800 combinations between slots/poles/phases/layers, analyzing the variability of the leakage factor for each condition and determining the optimal region for its minimization. The obtained results demonstrate that the leakage factor could be considerably reduced with the adoption of slightly asymmetrical windings, which represent a favorable option during the early design stage of electrical machines.
Prior Precision Modulates the Minimization of Auditory Prediction Error
2019
International audience; The predictive coding model of perception proposes that successful representation of the perceptual world depends upon canceling out the discrepancy between prediction and sensory input (i.e., prediction error). Recent studies further suggest a distinction to be made between prediction error triggered by non-predicted stimuli of different prior precision (i.e., inverse variance). However, it is not fully understood how prediction error with different precision levels is minimized in the predictive process. Here, we conducted a magnetoencephalography (MEG) experiment which orthogonally manipulated prime-probe relation (for contextual precision) and stimulus repetition…
Cluster-based RF fingerprint positioning using LTE and WLAN signal strengths
2017
Wireless Local Area Network (WLAN) positioning has become a popular localization system due to its low-cost installation and widespread availability of WLAN access points. Traditional grid-based radio frequency (RF) fingerprinting (GRFF) suffers from two drawbacks. First it requires costly and non-efficient data collection and updating procedure; secondly the method goes through time-consuming data pre-processing before it outputs user position. This paper proposes Cluster-based RF Fingerprinting (CRFF) to overcome these limitations by using modified Minimization of Drive Tests data which can be autonomously collected by cellular operators from their subscribers. The effect of environmental…
Continuous Monitoring of Parasitic Elements in Boost Converter Circuit
2021
The given paper explains the necessity of condition monitoring for DC/DC boost converter circuit. Further, an analytical model of circuit parasitic estimation is presented based on measured quantities in the circuit. The implementation of continuous estimation of circuit parasitic elements is analytically explained and verified by simulations and experimental results. Obtained results are acceptable for condition monitoring.
State Space-Vector Model of Linear Induction Motors including End-Effects and Iron Losses Part I: Theoretical Analysis
2020
This is the first part of the article, divided into two parts, dealing with the definition of a space-vector dynamic model of the linear induction motor (LIM) taking into consideration both the dynamic end-effects and the iron losses and its offline identification. This first part specifically treats the theoretical formulation of this model, which has been expressed in a state form, so to be, in perspective, suitably adopted for developing novel nonlinear control techniques, nonlinear observers as well as electrical losses minimization techniques. Besides the formulation of the dynamic model in space-vector state form, a steady-state analysis is proposed, highlighting the combined effects …
A General Investigation on the Differential Leakage Factor for Symmetrical and Asymmetrical Multiphase Winding Design
2020
This work provides an investigation based on a fast estimation of the degree of unbalance (D.U.%) and the differential leakage factor (&sigma
Reliability Estimation of Optimal Viscoelastic Composite Shells in Critical-Time Calculations
2003
The problem of reliability estimation for optimal viscoelastic composite shells in critical-time calculations is considered. The weight minimization of a viscoelastic composite shell, with constraints on deflections at the critical time, leads to a system deforming unstably, whose deflections grow in time with an increasing rate. A method for estimating the reliability of such shells in calculating the critical time is discussed. This time is regarded as a random variable depending on many, roughly equivalent, factors. An analysis of the reliability is carried out for different values of coefficients of variation, occurring in practice.
Functional A Posteriori Error Estimate for a Nonsymmetric Stationary Diffusion Problem
2015
In this paper, a posteriori error estimates of functional type for a stationary diffusion problem with nonsymmetric coefficients are derived. The estimate is guaranteed and does not depend on any particular numerical method. An algorithm for the global minimization of the error estimate with respect to an auxiliary function over some finite dimensional subspace is presented. In numerical tests, global minimization is done over the subspace generated by Raviart-Thomas elements. The improvement of the error bound due to the p-refinement of these spaces is investigated.
Epichristoffel Words and Minimization of Moore Automata
2014
This paper is focused on the connection between the combinatorics of words and minimization of automata. The three main ingredients are the epichristoffel words, Moore automata and a variant of Hopcroft's algorithm for their minimization. Epichristoffel words defined in [14] generalize some properties of circular sturmian words. Here we prove a factorization property and the existence of the reduction tree, that uniquely identifies the structure of the word. Furthermore, in the paper we investigate the problem of the minimization of Moore automata by defining a variant of Hopcroft's minimization algorithm. The use of this variant makes simpler the computation of the running time and consequ…