Search results for " minimization"
showing 10 items of 107 documents
Multiframe image restoration in the presence of noisy blur kernel
2009
We wish to recover an original image u from several blurry-noisy versions f k , called frames. We assume a more severe degradation model, in which the image u has been blurred by a noisy (stochastic) point spread function. We consider the problem of restoring the degraded image in a variational framework. Since the recovery of u from one single frame f is a highly ill-posed problem, we formulate two minimization problems based on the multiframe approach proposed for image super-resolution by Marquina-Osher [13]. Several experimental results for image restoration are shown, illustrating that the proposed models give visually satisfactory results.
Simple and Flexible Power Loss Minimizer With Low-Cost MCU Implementation for High-Efficiency Three-Phase Induction Motor Drives
2021
This paper presents a simple, practical and low-cost implementation of a power losses minimization algorithm for three-phase induction motors taking also into account both iron core losses and magnetic saturation. The algorithm evaluates, in real-time, the optimal direct axis magnetizing flux component for efficiency enhancement of the drive. A further advantage of the proposed technique is represented by a flexible and low-cost implementation by means of an ATMEL ATSAM3X8E microcontroller. The power loss minimization algorithm is tested preliminarily by means of several simulations, then, experimentally validated by applying the proposed control strategy on a 5.5 kW Field Oriented Control …
Homology modeling of an RNP domain from a human RNA-binding protein: Homology-constrained energy optimization provides a criterion for distinguishing…
1998
We have recently described an automated approach for homology modeling using restrained molecular dynamics and simulated annealing procedures (Li et al, Protein Sci., 6:956-970,1997). We have employed this approach for constructing a homology model of the putative RNA-binding domain of the human RNA-binding protein with multiple splice sites (RBP-MS). The regions of RBP-MS which are homologous to the template protein snRNP U1A were constrained by "homology distance constraints," while the conformation of the non-homologous regions were defined only by a potential energy function. A full energy function without explicit solvent was employed to ensure that the calculated structures have good …
Systematic conformational search analysis of the SRR and RRR epimers of 7-hydroxymatairesinol
2009
An extensive and systematic conformational search was performed on the two epimers of the natural lignan 7-hydroxymatairesinol (HMR), by means of a home-made Systematic Conformational Search Analysis (SCSA) code, designed to select more and more stable conformers through sequential geometry optimization of trial structures at increasing levels of calculation theory. In the present case, the starting molecular structures were selected by the semi-empirical AM1 method and filtered – i.e. decreased in number by choosing the more stable species – on the basis of their energy calculated by the HF method and the 6-31G(d) basis set. The geometries obtained were further refined by performing densit…
Are decisions in a real choice experiment consistent with reservation prices elicited with BDM 'auction'? The case of French baguettes
2014
Abstract The aim of this study was to compare consumer choices observed in a real choice experiment and their reservation prices elicited with the BDM mechanism in order to assess the rationality of participant behaviors. One hundred and seventy-seven participants tested four French baguettes in each task. For the real choice experiment, participants were faced with 17 scenarios (17 × 4 baguette-price combinations). In each method, participants could select a “no purchase” option. Comparing choices and reservation prices made it possible to assess the rationality of participant behaviors. From a strict economic standpoint, 50% of observed choices were fully rational. When one baguette was a…
Efficiency Improvement of Inverter-Fed Permanent Magnet Synchronous Motors
2003
In this paper a control algorithm for the efficiency improvement of inverter-fed permanent magnet synchronous motors (PMSMs) is presented. The proposed algorithm allows reducing the losses of the drive without reduction of its dynamic performances. In details, after recalling a dynamic model of the PMSM, which has been purposely modified and that takes into account the iron losses, the basic equations and the constraints to obtain the loss minimization are presented and discussed. Some simulations of a specific PMSM drive employing the proposed algorithm are performed. The results of these simulations show that the dynamic performances are maintained, and enhancement of the efficiency up to…
The management of sewage sludge: technologies, critical issue and perspectives
2022
The management of sludge produced by urban wastewater treatment plants has long been a problem for plant managers. This is due both to the growing costs for their disposal, and to the possible consequences that incorrect management may have on the performance of the wastewater treatment plant and on the environment. Further difficulties arose following the evolution of the European and national legislations, which regulates the management of sludge and its possible agronomic uses that introduced further checks and restrictions for this use. Several studies have been underway since last decades to reduce the extent of the problem. These focus on alternative objectives being aimed on the one …
Words, Trees and Automata Minimization
2013
In this paper we explore some connections between some combinatorial properties of words and the study of extremal cases of the automata minimization process. An intermediate role is played by the notion od word trees for which some properties of words are generalized. In particular, we describe an infinite family of binary automata, called word automata and constructed by using standard sturmian words and more specifically Fibonacci words, that represent the extremal case of some well known automata minimization algorithms, such as Moore’s and Hopcroft’s methods. As well as giving an overview of the main results in this context, the main purpose of this paper is to prove that, even if a re…
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…
Characterization of interior permanent magnet synchronous motors for loss model algorithm identification
2016
The paper provides the results of a detailed experimental study on the variations of the characteristics of an interior permanent magnet synchronous motor, when load, speed and/or magnetization conditions vary. In particular, the characterization is carried out by assessing, for several working conditions, the motor parameters that influence its efficiency. From the knowledge of the variability of these parameters, it is possible to develop a dynamic model of the motor, which accurately describes its behaviour and allows estimating the power losses for whatever speed and load. In order to validate the model, the values of the power losses obtained by using the model are compared with the va…