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Computational optimization, modelling and simulation : Recent trends and challenges
(2013) Yang, Xin She; Koziel, Slawomir; Leifsson, Leifur; Department of Engineering
Modelling, simulation and optimization form an integrated part of modern design practice in engineering and industry. Tremendous progress has been observed for all three components over the last few decades. However, many challenging issues remain unresolved, and the current trends tend to use nature-inspired algorithms and surrogate-based techniques for modelling and optimization. This 4th workshop on Computational Optimization, Modelling and Simulation (COMS 2013) at ICCS 2013 will further summarize the latest developments of optimization and modelling and their applications in science, engineering and industry. In this review paper, we will analyse the recent trends in modelling and optimization, and their associated challenges. We will discuss important topics for further research, including parameter-tuning, large-scale problems, and the gaps between theory and applications.
Verk
Multi-level CFD-based airfoil shape optimization with automated low-fidelity model selection
(2013) Koziel, Slawomir; Leifsson, Leifur; Department of Engineering
Computational fluid dynamic (CFD) models are ubiquitous in aerodynamic design. Variable-fidelity optimization algorithms have proven to be computationally efficient and therefore suitable to reduce high CPU-cost related to the design process solely based on accurate CFD models. A convenient way of constructing the variable-fidelity models is by using the high-fidelity solver, but with a varying degree of discretization and reduced number of flow solver iterations. So far, selection of the appropriate parameters has only been guided by the designer experience. In this paper, an automated lowfidelity model selection technique is presented. By defining the problem as a constrained nonlinear optimization problem, suitable grid and flow solver parameters are obtained. Our approach is compared to conventional methods of generating a family of variable-fidelity models. Comparison of the standard and the proposed approaches in the context of aerodynamic design of a transonic airfoil indicates that the automated model generation can yield significant computational savings.
Verk
Low-cost EM-simulation-driven multi-objective optimization of antennas
(2014) Bekasiewicz, Adrian; Koziel, Slawomir; Leifsson, Leifur; Department of Engineering
A surrogate-based method for efficient multi-objective antenna optimization is presented. Our technique exploits response surface approximation (RSA) model constructed from sampled low-fidelity antenna model (here, obtained through coarse-discretization EM simulation). The RSA model enables fast determination of the best available trade-offs between conflicting design goals. A low-cost RSA model construction is possible through initial reduction of the design space. Optimization of the RSA model has been carried out using a multi-objective evolutionary algorithm (MOEA). Additional response correction techniques have been subsequently applied to improve selected designs at the high-fidelity EM antenna model level. The refined designs constitute the final Pareto set representation. The proposed approach has been validated using an ultra-wideband (UWB) monocone and a planar Yagi-Uda antenna.
Verk
A scoping review of the Cryosphere’s ecosystem services, disservices, and related indicators
(Elsevier, 2025-06) Malinauskaite, Laura; Cook, David; Zaman, Hashim; Gomez-Baggethun, Erik; Faculty of Economics (UI); Hagfræðideild (HÍ); School of Social Sciences (UI); Félagsvísindasvið (HÍ)
The cryosphere, which refers to the parts of the Earth’s surface where water is in solid form, is a major contributor to human wellbeing through the provision of vital ecosystem services. These include, e.g., groundwater recharge, water storage and purification, climate regulation, and diverse cultural and spiritual benefits. A systematized classification of ecosystem services can be used to define, measure, and value the ways in which the cryosphere contributes to society and to communicate these benefits in a clear, transparent and scientifically sound way, yet, it has been missing to date. This study builds on previous literature exploring the cryosphere’s positive and negative impacts on human wellbeing in the context of rapid climate change. It further organises this knowledge on a global scale with a view to enhancing scientific exploration and policy guidance, along with facilitating comparability between different studies. Our research applies the Search-Appraisal-Synthesis-Analysis (SALSA) literature review method and the Common International Classification of Ecosystem Services (CICES) to source and systemise the existing information on ecosystem services and disservices provided by the cryosphere, and possible indicators for monitoring their changes are identified. A total of 30 ecosystem services and 10 disservices were identified, together with indicators that could be used to monitor their trends in biophysical, economic, and sociocultural terms. Our research finds that the cryosphere continues to provide vital ecosystem services despite accelerated retreat of glaciers and other cryospheric components, but also an increasing amount of ecosystem disservices because of global climate change. Monitoring trends in the cryosphere’s contributions to human wellbeing has the potential to inform adaptive governance in fast-changing cryospheric environments.
Verk
The Genuine Progress Indicator for the transition economies of the Baltic States: reflections on economic welfare and methodological choices
(Elsevier, 2026-09) Malinauskaite, Laura; Cook, David; Davíðsdóttir, Brynhildur; Faculty of Economics (UI); Hagfræðideild (HÍ); School of Social Sciences (UI); Félagsvísindasvið (HÍ)
The Baltic States of Estonia, Latvia, and Lithuania have experienced rapid Gross Domestic Product (GDP) growth since the collapse of the Soviet Union and subsequent transition from planned to market economy, reporting increasing levels of consumption and subjective wellbeing but persistent income inequality, which raises the question of whether economic expansion has translated into genuine welfare improvements. The study provides the first application of an updated Genuine Progress Indicator (GPI) framework to the Baltic States for the period 1995-2023. To assess the robustness of the results, a sensitivity analysis of the components with the greatest influence on GPI values was conducted: valuation of lei-sure time, the cost of carbon, and the income inequality adjustment. The analysis reveals that economic welfare measured by the GPI has generally exceeded GDP across all three countries in the study period, apart from 2023 in Estonia and Lithuania, offering indications that the welfare returns of additional economic growth might be diminishing. However, the extent to which the GPI exceeds or falls below GDP varies considerably depending on pa-rameter choices. The sensitivity of the GPI to assumptions regarding hourly wages, carbon cost, and inequality baselines highlights methodological challenges that makes cross-country comparisons difficult. These findings caution against uncritical use of the GPI in pol-icy settings and highlight the need for methodological standardisation and clearer valuation guidelines if the metric is to serve as a credible tool for assessing progress beyond GDP.

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