Search results for "cost"

Solitary Waves for the Assessment of Thermal Stress and Neutral Temperature in Slender Structures

2015

Slender columns and continuous welded rails subjected to compressive stress are common in many civil structures. The rapid in-situ measurement of this stress may be of interest to prevent structural anomalies such as buckling. In this article, the authors describe the coupling mechanism between highly nonlinear solitary waves (HNSWs) propagating along an L-shaped granular system and a beam in contact with the granular medium. The aim is the evaluation of HNSWs as a tool to measure stress in thermally loaded structures and to estimate the neutral temperature, i.e. the temperature at which this stress is null. The authors investigated numerically and experimentally one chain of spherical part…

A symmetric nonlocal damage theory

2003

The paper presents a thermodynamically consistent formulation for nonlocal damage models. Nonlocal models have been recognized as a theoretically clean and computationally efficient approach to overcome the shortcomings arising in continuum media with softening. The main features of the presented formulation are: (i) relations derived by the free energy potential fully complying with nonlocal thermodynamic principles; (ii) nonlocal integral operator which is self-adjoint at every point of the solid, including zones near to the solid's boundary; (iii) capacity of regularizing the softening ill-posed continuum problem, restoring a meaningful nonlocal boundary value problem. In the present app…

Fractional calculus in solid mechanics: local versus non-local approach

2009

Several enriched continuum mechanics theories have been proposed by the scientific community in order to develop models capable of describing microstructural effects. The aim of the present paper is to revisit and compare two of these models, whose common denominator is the use of fractional calculus operators. The former was proposed to investigate damage in materials exhibiting a fractal-like microstructure. It makes use of the local fractional derivative, which turns out to be a powerful tool to describe irregular patterns such as strain localization in heterogeneous materials. On the other hand, the latter is a non-local approach that models long-range interactions between particles by …

Presentazione

2007

CZT-Based Harmonic Analysis in Smart Grid Using Low-Cost Electronic Measurement Boards

2023

This paper validates the use of a harmonic analysis algorithm on a microcontroller to perform measurements of non-stationary signals in the context of smart grids. The increasing presence of electronic devices such as inverters of distributed generators (DG), power converters of charging stations for electric vehicles, etc. can drain non-stationary currents during their operation. A classical fast Fourier transform (FFT) algorithm may not have sufficient spectral resolution for the evaluation of harmonics and inter-harmonics. Thus, in this paper, the implementation of a chirp-Z transform (CZT) algorithm is suggested, which has a spectral resolution independent from the observation window. T…

Fossil Fuel and Biofuel Boilers in Ukraine: Trends of Changes in Levelized Cost of Heat

2022

An increase in the share of renewables in heat supply systems is a promising direction to reach sustainable development goals and decarbonization. Decision makers should consider various factors, including energy market prices, the availability of biofuels, boiler and auxiliary equipment costs, logistic costs, and the taxation system. In the European Union, the energy crisis causes a rapid increase in fossil fuel prices. Moreover, the use of fossil fuels results in greenhouse gas emissions, which threatens the achievement of sustainable development goals. We studied the influence of the delivery cost and the value of environmental tax rates on the levelized cost of heat. Low-capacity boiler…

Optimistic NAUTILUS navigator for multiobjective optimization with costly function evaluations

2022

AbstractWe introduce novel concepts to solve multiobjective optimization problems involving (computationally) expensive function evaluations and propose a new interactive method called O-NAUTILUS. It combines ideas of trade-off free search and navigation (where a decision maker sees changes in objective function values in real time) and extends the NAUTILUS Navigator method to surrogate-assisted optimization. Importantly, it utilizes uncertainty quantification from surrogate models like Kriging or properties like Lipschitz continuity to approximate a so-called optimistic Pareto optimal set. This enables the decision maker to search in unexplored parts of the Pareto optimal set and requires …

The finger of Beelzebub. The consecration of judicial review of constitutionality in Portugal in 1911

2022

Without entirely breaking with the political review of constitutionality established in the 19th century, Portugal, which became a republic after the October 1910 revolution, decided to enshrine judicial review of constitutionality in its 1911 Constitution. The choice of the American model of diffuse review was intended to break with the main guarantee offered in the days of 'granted constitutionalism', when the moderating power of the King acted as guarantor of the Constitution alongside the political chambers. This was the aim of the promoter of this legal revolution, the law professor Afonso Costa, a strong man of the First Republic, who was able to convert his initially hostile republic…

La matriz de análisis de políticas con datos eficientes: evaluación de la rentabilidad del cultivo del arroz

2008

This paper combines policy analysis matrix and data envelopment analysis techniques to model the analysis of profitability from farming. Policy analysis matrices are computed for a sample of rice growers located in the wetland of the Albufera (Eastern Spain) under observed conventional and profit-efficient farming conditions. While conventional analysis points to a lack of profitability, farmers are shown to make positive profits at private and social prices when data reflecting efficiency adjustments are used in the analysis. The main conclusion is that the usefulness of the policy analysis matrix might be substantially enhanced by simulating profitability after efficiency-improving manage…

La configuración del derecho de asilo en la Unión Europea a la luz renovadora del derecho a no sufrir tortura o tratos inhumanos y degradantes

2018

The Chapter analyzes the EU Court of Justice case law on Aliens' Protection Regimes in light of the EU Charter of Fundamental Rights and of the European Convention of Human Rights focusing on: a) the impact of non refoulement and protection from risk of torture and inhuman or degrading treatments principles; b) procedural safeguards of right to seek "asylum" on the implementation of EU "Dublin regulation". Both aspects are taken into exam in the perspective of identifying common EU standards of protection of fundamental rights of the persons in the process of judicial implementation of the EU Charter of Fundamental Rights lead by the European Union Court of Justice (expecially after the ent…