Periodic train timetable expansion: An integrated model of multi-period train service selection and rolling stock circulation with time-varying passenger demand

The periodic train timetable is one of the most widely used train timetables in passenger railway systems worldwide. However, how to expand well-coordinated daily train services from a single-period timetable pattern is rarely studied. This paper develops a multi-objective mixed integer programming model to solve the periodic train timetable...

Exploring revenue-driven wind turbine design

Traditionally, wind turbine and wind farm designs have been optimized to minimize the cost of energy. Such a design would make sense when bidding in price-based auctions. However, in a future with a high share of renewables and zero subsidies, the wind farm developer could be completely exposed to the volatility of market prices, where the price...

Climate impact mitigation potential of european air traffic

Air traffic contributes to anthropogenic global warming by about 5% due to CO2 emissions (about 1/3) and non-CO2 effects (about 2/3) primarily caused by emissions of NOx and water vapour as well as the formation of contrails. Since aviation is expected to maintain its trend to grow over the next decades, mitigation measures are required...

Comparison of various aircraft routing strategies using the air traffic simulation model airtraf 2.0

A climate-optimized routing is expected as an operational measure to reduce the climate impact of aviation, whereas this routing causes extra aircraft operating costs. This study performs some air traffic simulations of nine aircraft routing strategies which include the climate-optimized routing, and examines characteristics of those routings. A...

Assessing the climate impact of formation flights

Emissions of aviation include CO2, H2O, NOx and particles. While CO2 has a long atmospheric residence time and is uniformly distributed in the atmosphere, non-CO2 gases, particles and their products have short atmospheric residence times and are heterogeneously distributed. Their climate effects depend on chemical and meteorological background...

Topology optimization with overhang filter considering accessibility of supports

Optimization modeling of regional energy systems considering coordination mechanisms

Dutch regional municipalities increasingly take an active role in the transition to more sustainable and autonomous energy supply systems, using local energy sources like wind, solar and biomass. The ambition, on the one hand, concerns how an optimal local energy supply system can be designed such that local energy targets can be realized with...

Optimization of flood risk reduction through multiple lines of defence

loods can have a huge impact on the regions they affect. The impact of these disasters can be reduced with a flood risk management system. Flood-prone regions often require a combination of interventions to reduce the risk to an acceptable level. The amount of risk reduction provided by various interventions can be quantified using probabilistic...

Topology optimization of part and support structures for additive manufacturing considering machining forces

Computational time issues of AM process simulations with a view to large-scale topology optimization

Overhang free topology optimization applied to flow optimization

A semi-analytical thermal model of selective laser melting process

A computationally efficient process modelling approach for selective laser melting

Overhang angle control and optimal part orientation in topology optimization for additive manufacturing