Search results for "Benchmark"
showing 10 items of 310 documents
Economic and Technical Efficiency of Drinking Water Systems: An Empirical Approach for Spain
2009
The objective of this paper is to analyze the efficiency of drinking water systems. Efficient performance, both in technical and economic terms guarantee minimum water losses in the network and reduced tariffs for the users. An analytical benchmarking methodology based on non-radial measures considering water losses as undesirable output gives us an efficiency indicator for each input used in the water supply process. These indicators, obtained by means of mathematical programming techniques, are used to rank suppliers' activity. The relation between the efficiency in the activity of the companies and the establishment of different tariffs is also analyzed. An empirical application is carry…
The finite element implementation of 3D fractional viscoelastic constitutive models
2018
Abstract The aim of this paper is to present the implementation of 3D fractional viscoelastic constitutive theory presented in Alotta et al., 2016 [1]. Fractional viscoelastic models exactly reproduce the time dependent behaviour of real viscoelastic materials which exhibit a long “fading memory”. From an implementation point of view, this feature implies storing the stress/strain history throughout the simulations which may require a large amount of memory. We propose here a number of strategies to effectively limit the memory required. The form of the constitutive equations are summarized and the finite element implementation in a Newton-Raphson integration scheme is described in detail. …
Non-linear System Identification with Composite Relevance Vector Machines
2007
Nonlinear system identification based on relevance vector machines (RVMs) has been traditionally addressed by stacking the input and/or output regressors and then performing standard RVM regression. This letter introduces a full family of composite kernels in order to integrate the input and output information in the mapping function efficiently and hence generalize the standard approach. An improved trade-off between accuracy and sparsity is obtained in several benchmark problems. Also, the RVM yields confidence intervals for the predictions, and it is less sensitive to free parameter selection. Teoría de la Señal y Comunicaciones
Assessment of building energy modelling studies to meet the requirements of the new Energy Performance of Buildings Directive
2020
Abstract The cost optimal method (COM) as applied in the Energy Performance of Buildings Directive (EPBD) uses “non-calibrated deterministic reference buildings (RBs)”. Such RBs are defined with single envelope and equipment parameter values, for which calibration with actual building stock energy performance (EP) is not undertaken. Thus, it is not possible to visualise the effect of uncertainties or diversity in the input parameters on cost-optimal level benchmarks and to verify the choice of RBs. The paper proposes an update to the COM via use of “Probabilistic Bayesian calibrated RBs” to handle uncertainties and produce more realistic cost optimal levels to support policy makers in devis…
Soil erosion modelling: A bibliometric analysis.
2021
16 Pags.- 12 Figs.- 8 Tabls.
Learning Automata-Based Solutions to the Multi-Elevator Problem
2019
In the last century, AI has been the topic of interest in many areas, where the focus was on mimicking human behaviour. It has been researched to be incorporated into different domains, such as security, diagnosis, autonomous driving, financial prediction analysis and playing games such as chess and Go. They also worked on different subfields of AI such as machine learning, deep learning, pattern recognition and other relevant subfields. Our work in a previous paper [1] focused on a problem that has not been tackled using AI before, which is the elevator-problem. In which we try to find the optimal parking floor for the elevator for the single elevator problem. In this paper, our work exten…
A Survey of Methods to Interpolate, Distribute and Extra- polate Time Series
2010
This survey provides an overview with a broad coverage of the literature on methods for temporal disaggregation and benchmarking. Dozens of methods, procedures and algorithms have been proposed in the statistical and economic literature to solve the problem of transforming a low-frequency series into a high-frequency one. This paper classifies and reviews the procedures, provides interesting discussion on the history of the methodological development in this literature and permits to identify the assets and drawbacks of each method, to comprehend the current state of art on the subject and to identify the topics in need of further development. It would be useful for readers who are interest…
Fuzzy ServPerf model combined with ELECTRE III to comparatively evaluate service quality of international airports in Sicily
2015
In this paper a new approach was proposed so as to comparatively evaluate the quality of service alternatives. In particular, a fuzzy extension of the ServPerf service conceptual model was considered to estimate quality scores of fundamental service criteria, whereas the non-compensative multi-criteria decision-making ELECTRE III method was employed to point out the quality ranking of service alternatives on the basis of which the comparative service quality analysis was performed. In order to show the effectiveness of the proposed approach, an empirical study concerning service quality evaluation of the three international airports in Sicily (Italy) was conducted with detailed proposals fo…
Evolving e-government benchmarking to better cover technology development and emerging societal needs
2012
Many international e-government benchmarks seek to measure progress towards various versions of a digital society, and in this endeavor include a component of e-government. But because comparable international e-government data are scarce, most reports rely on the United Nations E-Government Development Index, specifically its Online Service Index as a benchmark. However, this assessment only captures national level initiatives at a broad level and does not link evaluation to outcomes and impacts, i.e. e-government performance relative to investment.This paper briefly reviews the current UN framework and assesses how it can evolve to meet new demands, such as calls to better connect investm…
Assessing the quality of service to customers provided by water utilities: A synthetic index approach
2017
Abstract Currently, water and sewer companies face the challenge of improving their quality of service to customers (QSC). Performance indicators are essential to monitor and benchmark the QSC of water companies; however, individual indicators do not provide a holistic evaluation of the quality of water and sewer services provided to customers. This study proposes an innovative QSC index based on distance-function techniques that makes it possible to compare changes in the QSC of water companies among locations and temporal periods. A case study assesses changes in QSC for a sample of Chilean water and sewer companies from 2007 to 2014. The results show that in spite of the efforts made by …