Search results for "multi-objective"

showing 10 items of 220 documents

Technical and Economical Analysis of Different Measures for Efficient Operation of a Distribution Network in a Mediterranean Island

2006

The paper performs a technical and economical comparison of different measures to improve the efficiency of a MV system for power distribution in the Mediterranean island of Lampedusa. The study takes into consideration three possible measures: 1) rated voltage increase from 10 kV to 20 kV; 2) reactive power compensation with fixed capacitor banks; 3) reactive power compensation with switchable capacitor banks. While the study of the first two considered measures is carried out with classical design methods, the optimal reactive design with switchable capacitor banks is carried out by means of a specific software set up at the DIEET and implementing the multiobjective optimization genetic a…

EngineeringOptimization problembusiness.industryControl engineeringAC powerMulti-objective optimizationReliability engineeringCompensation (engineering)Power (physics)law.inventionCapacitorlawGenetic algorithmDesign methodsbusinessProceedings of the 41st International Universities Power Engineering Conference
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Design of complex sheet metal forming processes: a new computer aided progressive approach

2010

The growing interest in sheet metal stamping processes, particularly in automotive industry, led to three main issues in this field: request of very complex shapes; growing interest in springback control; solution of multi-objective problems. This makes the design of the sheet metal stamping processes very difficult, since the number of both design variables and design objectives are progressively increased; therefore, proper design methodologies to reduce times and costs are highly required. In this paper, an innovative design approach able to manage and optimize complex stamping operations is proposed. In particular, a progressive design approach based on the integration between numerical…

Engineeringbusiness.industryAutomotive industryForming processesSheet metal stampingComputational intelligenceStampingManufacturing engineeringMoving least square approximationDesign objectivevisual_artComputer-aidedvisual_art.visual_art_mediumMulti-objective optimisationGeneral Materials ScienceResponse surface methodologybusinessSheet metalSettore ING-IND/16 - Tecnologie E Sistemi Di Lavorazione
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Multi-objective strategies for management and design of distributed electric storage systems in a Mediterranean island

2013

The paper proposes an analytical study about the design and operation of distributed Electrical Storage Systems(ESS) in an active distribution network supplying a Mediterranean island, according to different criteria. The approach is based on the application of a multi-objective optimization algorithm (NSGA-II) that outputs a set of optimized schedules of the ESS in different configurations when operated according to different criteria (minimum energy losses in the grid, total generation cost, greenhouse gas emissions, limiting the fluctuations of the generation from fossil fuel plants). Moreover the variability of the voltage profile has been investigated also by a comparison with a refere…

Engineeringbusiness.industryFossil fuelComputerApplications_COMPUTERSINOTHERSYSTEMSControl engineeringGridActive Distribution NetworkEnergy storageReliability engineeringMulti-objective Optimization;Active Distribution Networks;ESSSettore ING-IND/33 - Sistemi Elettrici Per L'EnergiaStand-alone power systemDistributed generationGreenhouse gasActive Distribution NetworksESSbusinessMulti-objective OptimizationEnergy (signal processing)Voltage
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On thermoeconomics of energy systems at variable load conditions: integrated optimization of plant design and operation

2007

Abstract Thermoeconomics has been assuming a growing role among the disciplines oriented to the analysis of energy systems, its different methodologies allowing solution of problems in the fields of cost accounting, plant design optimisation and diagnostic of malfunctions. However, the thermoeconomic methodologies as such are particularly appropriate to analyse large industrial systems at steady or quasi-steady operation, but they can be hardly applied to small to medium scale units operating in unsteady conditions to cover a variable energy demand. In this paper, the fundamentals of thermoeconomics for systems operated at variable load are discussed, examining the cost formation process an…

ExergyEngineeringPrimary energyRenewable Energy Sustainability and the Environmentbusiness.industryThermoeconomics has been assuming a growing role among the disciplines oriented to the analysis of energy systems its different methodologies allowing solution of problems in the fields of cost accounting plant design optimisation and diagnostic of malfunctions. However the thermoeconomic methodologies as such are particularly appropriate to analyse large industrial systems at steady or quasisteady operation but they can be hardly applied to small to medium scale units operating in unsteady conditions to cover a variable energy demand. In this paper the fundamentals of thermoeconomics for systems operated at variable load are discussed examining the cost formation process and separately the cost fractions related to capital depreciation (which require additional distinctions with respect to plants in steady operation) and to exergy consumption. The relevant effects of the efficiency penalty due to off design operation on the exergetic cost of internal flows are also examined. An original algorithm is proposed for the integrated optimization of plant design and operation based on an analytical solution by the Lagrange multipliers method and on a multi-objective decision function expressed either in terms of net cash flow or primary energy saving. The method is suitable for application in complex energy systems such as ‘‘facilities of components of a same product’’ connected to external networks for power or heat distribution. For demonstrative purposes the proposed thermoeconomically aided optimization is performed for a grid connected trigeneration system to be installed in a large hotel.Energy Engineering and Power TechnologyCost accountingThermoeconomicsGridEnergy conservationVariable (computer science)symbols.namesakeFuel TechnologyNuclear Energy and EngineeringLagrange multipliersymbolsProcess engineeringbusinessSimulation
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A Feature Rich Distance-Based Many-Objective Visualisable Test Problem Generator

2019

In optimiser analysis and design it is informative to visualise how a search point/population moves through the design space over time. Visualisable distance-based many-objective optimisation problems have been developed whose design space is in two-dimensions with arbitrarily many objective dimensions. Previous work has shown how disconnected Pareto sets may be formed, how problems can be projected to and from arbitrarily many design dimensions, and how dominance resistant regions of design space may be defined. Most recently, a test suite has been proposed using distances to lines rather than points. However, active use of visualisable problems has been limited. This may be because the ty…

Flexibility (engineering)Mathematical optimizationeducation.field_of_studyComputer sciencevisualisointiMulti-objective test problemsPopulationPareto principleevoluutiolaskenta0102 computer and information sciences02 engineering and technology01 natural sciencesmonitavoiteoptimointiSet (abstract data type)test suiteRange (mathematics)010201 computation theory & mathematicsevolutionary optimisation0202 electrical engineering electronic engineering information engineeringTest suite020201 artificial intelligence & image processingPoint (geometry)benchmarkingeducationGenerator (mathematics)
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An Interactive Simple Indicator-Based Evolutionary Algorithm (I-SIBEA) for Multiobjective Optimization Problems

2015

This paper presents a new preference based interactive evolutionary algorithm (I-SIBEA) for solving multiobjective optimization problems using weighted hypervolume. Here the decision maker iteratively provides her/his preference information in the form of identifying preferred and/or non-preferred solutions from a set of nondominated solutions. This preference information provided by the decision maker is used to assign weights of the weighted hypervolume calculation to solutions in subsequent generations. In any generation, the weighted hypervolume is calculated and solutions are selected to the next generation based on their contribution to the weighted hypervolume. The algorithm is compa…

Flexibility (engineering)Set (abstract data type)Mathematical optimizationComputer scienceBenchmark (computing)Evolutionary algorithmmultiobjective optimizationInteractive evolutionary computationevolutionary algorithmsinteractive methodsMulti-objective optimizationEvolutionary programmingPreference
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Simplified Energy Model and Multi-Objective Energy Consumption Optimization of a Residential House

2022

Featured Application: The potential application of the proposed model is a computationally inexpensive semi- or fully automated system for the optimization of operation in residential buildings in terms of energy consumption. Some analyses state that buildings contribute to overall energy consumption by 20–40%, which, in the context of the recent geopolitical energy crisis, makes them a critical issue to study. Finding solutions for better energy management in buildings can have a significant impact on the energy sector, thus reducing EU energy dependencies and contributing to the fulfillment of the REPowerEU goals. This paper focuses on proposing a simplified model of a residential house c…

Fluid Flow and Transfer ProcessesSettore ING-IND/33 - Sistemi Elettrici Per L'EnergiaProcess Chemistry and Technologybuilding energy model energy demand multi-objective optimization residential building simulation weather forecast uncertaintyGeneral Engineeringresidential building simulation; building energy model; energy demand; weather forecast uncertainty; multi-objective optimizationGeneral Materials ScienceInstrumentationComputer Science ApplicationsApplied Sciences; Volume 12; Issue 20; Pages: 10212
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A heuristic fuzzy algorithm for assessing and managing tourism sustainability

2019

“Smartness” and “sustainability” are gaining growing attention from both practitioners and policy makers. “Smartness” and “sustainability” assessments are of crucial importance for directing, in a systemic perspective, the decision-making process toward sustainability and smart growth objectives. Sustainability assessment is a major challenge due to the multidisciplinary aspects involved that make the evaluation process complex and hinder the effectiveness of available monitoring tools. To achieve the assessment objective, we introduce an enhanced fuzzy logic-based framework for handling the inherent uncertainty and vagueness of the involved variables: we apply our approach to Italy, and we…

Fuzzy sets0209 industrial biotechnologyProcess (engineering)Computer science02 engineering and technologyEvolutionary algorithmsFuzzy logicTheoretical Computer Science020901 industrial engineering & automationQuality of lifeMultidisciplinary approachEvolutionary algorithm0202 electrical engineering electronic engineering information engineeringSustainable tourismTourism sustainabilitySettore SECS-S/06 - Metodi mat. dell'economia e Scienze Attuariali e FinanziarieEvolutionary algorithms; Fuzzy sets; Multi-objective optimization; Sustainability; Threshold accepting;Smart growthThreshold acceptingMulti-objective optimizationSustainabilityRisk analysis (engineering)SustainabilityFuzzy set020201 artificial intelligence & image processingGeometry and TopologySettore MAT/09 - Ricerca OperativaScience technology and societySoftwareTourismSoft Computing
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Exploring Multiobjective Optimization for Multiview Clustering

2018

We present a new multiview clustering approach based on multiobjective optimization. In contrast to existing clustering algorithms based on multiobjective optimization, it is generally applicable to data represented by two or more views and does not require specifying the number of clusters a priori . The approach builds upon the search capability of a multiobjective simulated annealing based technique, AMOSA, as the underlying optimization technique. In the first version of the proposed approach, an internal cluster validity index is used to assess the quality of different partitionings obtained using different views. A new way of checking the compatibility of these different partitioning…

General Computer ScienceComputer science02 engineering and technologycomputer.software_genreMulti-objective optimizationCluster validity index020204 information systemsSimulated annealingNew mutation0202 electrical engineering electronic engineering information engineeringA priori and a posteriori020201 artificial intelligence & image processingData miningCluster analysisMultiple viewcomputerACM Transactions on Knowledge Discovery from Data
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Assessing the Performance of Interactive Multiobjective Optimization Methods

2021

Interactive methods are useful decision-making tools for multiobjective optimization problems, because they allow a decision-maker to provide her/his preference information iteratively in a comfortable way at the same time as (s)he learns about all different aspects of the problem. A wide variety of interactive methods is nowadays available, and they differ from each other in both technical aspects and type of preference information employed. Therefore, assessing the performance of interactive methods can help users to choose the most appropriate one for a given problem. This is a challenging task, which has been tackled from different perspectives in the published literature. We present a …

General Computer ScienceComputer sciencepäätöksenteko0211 other engineering and technologiespreference information02 engineering and technologyMachine learningcomputer.software_genreMulti-objective optimizationTheoretical Computer ScienceTask (project management)menetelmätoptimointi0202 electrical engineering electronic engineering information engineering021103 operations researchbusiness.industryinteractive methodsmonitavoiteoptimointidecision-makersPreferenceVariety (cybernetics)Multiobjective optimization probleminteraktiivisuusmultiobjective optimization problems020201 artificial intelligence & image processingperformance assessmentArtificial intelligencebusinesscomputerACM Computing Surveys
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