Search results for "optimization"
showing 10 items of 2824 documents
Optimal design of steel frames accounting for buckling
2013
A formulation of a special design problem devoted to elastic perfectly plastic steel frame structures subjected to different combinations of static and dynamic loads is presented. In particular, a minimum volume design problem formulation is presented and the structure is designed to be able to elastically behave for the assigned fixed loads, to elastically shakedown in presence of serviceability load conditions and to prevent the instantaneous collapse for suitably chosen combinations of fixed and ultimate seismic loadings as well as of fixed and wind actions. The actions that the structure must suffer are evaluated by making reference to the actual Italian seismic code. The dynamic respon…
An original multi-objective criterion for the design of small-scale polygeneration systems based on realistic operating conditions
2008
The optimal design and operation of cogeneration and trigeneration systems for buildings applications is a complex issue, which has been investigated by several different approaches. Both the two basic management strategies, namely heat-tracking and electricity-tracking, have advantages and drawbacks in terms of operating results and may lead the plant designer either to undersize or oversize the CHP unit with respect to the optimal lay-out. Experimental works have demonstrated how the actual on-site performance of small-scale polygeneration systems significantly differs from their expected operation, due to the need for a regular plant operation and the effects of outages for scheduled or …
Multi-objective discrete optimization of laminated structures
2002
Abstract The paper is dedicated to the multi-objective optimal design of laminated composite structures. In order to provide sound-engineering designs, a few alternative and/or conflicting objectives must be taken into account. It is reasonable to consider the multi-objective optimization as a sensible enrichment with respect to single objective optimization, since the solutions are enforced to result optimal at the same time with respect to different objectives. Multi-objective optimization methods gained in the last years a growing interest in engineering, due to the possibility to determine a design possessing at the same time optimality with respect to different conflicting requirements…
A double-shell design approach for multiobjective optimal design of microgrids
2010
This work develops a new double shell approach to optimal design for multi-objective optimally managed systems. The cost of each design solution can be defined by the evaluation of operational issues and capital costs. In most systems, the correct definition of operational issues can be deduced by means of the solution of a multi-objective optimization problem. The evaluation of each design solution must thus be deduced using the outcome of a multi-objective optimization run, namely a Pareto hyper-surface in the n-dimensional space of operational objectives. In the literature, the design problem is usually solved by considering a single objective formulation of the operational issue. In thi…
Comparison between Entropy and Resilience as Indirect Measures of Reliability in the Framework of Water Distribution Network Design
2014
Abstract The aim of this paper is to investigate which between the entropy and resilience indices represents a better indirect measure of reliability in the framework of water distribution network design. The methodology adopted consisted of (a) multi-objective optimizations performed in order to minimize costs and maximize reliability, expressed by means of one of the indirect indices at time; (b) retrospective performance assessment of the solutions of Pareto fronts obtained. Two case studies of different topological complexity were considered. Results showed that indices based on energetic concepts (resilience and modified resilience) represent a better compact estimate of reliability th…
Fixed domain approaches in shape optimization problems with Dirichlet boundary conditions
2009
Fixed domain methods have well-known advantages in the solution of variable domain problems including inverse interface problems. This paper examines two new control approaches to optimal design problems governed by general elliptic boundary value problems with Dirichlet boundary conditions. Numerical experiments are also included peerReviewed
Optimal tuning of tuned liquid column damper systems in random vibration by means of an approximate formulation
2014
Passive control devices are often added to slender and flexible systems in order to increase their structural safety. Several types of devices have been proposed in order to reduce the dynamic responses of different kind of structural systems. Among them, the tuned liquid column damper (TLCD) proved to be very effective in reducing vibration of various type of structures by means of a combined action which involves the motion of the liquid mass within the tube. The restoring force, in particular, is produced by the force of gravity acting on the liquid and the damping effect is generated by the hydrodynamic head losses that arise during the motion of the liquid inside the TLCD. Since the in…
Design Optimization Automation for Luminaire Reflectors Using COMSOL Multiphysics and Performance Comparison Against Zemax Opticstudio
2019
This work showcases the complete design pipeline based on COMSOL Multiphysics for one of the luminaire models manufactured by Vizulo. Generation of optimization targets, ray tracing models and utilized optimization algorithms are described. The authors also evaluate the performance of COMSOL against Zemax OpticStudio Premium, a specialized optics design suite widely used by the optics industry. Out-of-the-box version of both packages are tested: ray tracing and optimization performance are compared. It is found that, while OpticStudio' ray tracer is by far superior, OpticStudio is greatly outperformed by COMSOL in optimization tasks for considered problems. Other aspects of both packages ar…
Regularity of sets under a reformulation in a product space of reduced dimension
2023
Different notions on regularity of sets and of collection of sets play an important role in the analysis of the convergence of projection algorithms in nonconvex scenarios. While some projection algorithms can be applied to feasibility problems defined by finitely many sets, some other require the use of a product space reformulation to construct equivalent problems with two sets. In this work we analyze how some regularity properties are preserved under a reformulation in a product space of reduced dimension. This allows us to establish local linear convergence of parallel projection methods which are constructed through this reformulation.
Monge Problem on infinite dimensional Hilbert space endowed with suitable Gaussian measure
2014
In this paper we solve the Monge problem on infinite dimensional Hilbert space endowed with a suitable Gaussian measure, that satisfies the Lebesgue differentiation theorem.