Search results for "Optimisation"

(No title)

2003

The aim of this work is to study multiobjective optimization problems with or without dynamics and the generalized Bolza problem and its applications. After having pointed out some concepts of nonsmooth analysis, we begin the first part of this thesis with the existence of Lagrange multipliers for multiobjective optimization problems in infinite dimension with a general preference. We introduce the regularity of preference and use calmness qualification condition we establish the existence of Karush-Kuhn-Tucker multipliers. This allows us to obtain Fritz-John multipliers in terms of the approximate subdifferential by Ioffe. Then we derive similar results when the preference is defined by a …

Mācību sasniegumus ietekmējošie faktori Latvijas vispārizglītojošās skolās

2017

Promocijas darba mērķis ir izpētīt datus par izglītojamo mācību sasniegumiem starptautiski salīdzinošajos izglītības pētījumos, valsts pārbaudes darbos un izglītojamo gada vērtējumiem mācību priekšmetos, sniegt rekomendācijas par iespējamiem Latvijas vispārējās izglītības optimizācijas virzieniem. Promocijas darba rezultātā ir izstrādāti ierosinājumi, kuru īstenošana ļautu paaugstināt izglītojamo mācību sasniegumus vispārējās izglītības posmā. Promocijas darbu veido ievads, sešas savstarpēji saistītas nodaļas par četrām tēmām un nobeigums. Atslēgas vārdi: vispārējā izglītība, izglītības sistēmas optimizācija, mācību sasniegumi, kavējumi, skolas un klases lielums, obligātās izglītības uzsākš…

A multi-objective Pareto design approach for simultaneous control of thinning and springback in complex stamping operations.

2009

Abstract In sheet metal forming operations design, optimization problems have to be solved in order to reach optimal process conditions. In these problems, there are some crucial issues to be taken into account: - most of the problems are multi objective problems, generally characterized by conflicting objectives: the definition of proper parameters aimed to prevent both springback and fracture is a typical example of an optimization problem in sheet metal forming characterized by conflicting goals; - in an industrial environment a great interest would be focused on the availability of a cluster of possible optimal solutions instead of a single “almost optimal” solution. Taking into account…

DYNAMIC ANALYSIS OF MOTORCYCLE BEHAVIOUR ON THE ROAD WITH STEERING PLATE STRUCTURAL OPTIMISATION

2005

COMMUNITY DETECTION IN TRIPARTITE NETWORKS OF UNIVERSITY STUDENT MOBILITY FLOWS

2021

The purpose of this study is to explore how the multimode network approach can be used to analyse network patterns derived from student mobility flows. We define a tripartite network based on a three-mode data structure, consisting of Italian provinces of residence, universities and fields of study, with student exchanges representing the links between them. A comparison of algorithms for detecting communities from tripartite networks based on modularity optimization is provided, revealing relevant information about the phenomenon under analysis over time. The findings are applied to a real dataset containing micro-level longitudinal information on Italian university students’ careers.

Optimisation algorithms in the case of mineral detection using Raman Analysis

2013

Abstract Raman analysis can be used to analyse the existence of minerals in an ore sample. Especially the interest here is to analyse given ore sample rapidly, to find out what minerals it contains. Rapid analysis would enable more rapid exploration of minerals as analysis could be carried out on-site. For this study, ore samples were collected from two mines in Northern Finland, Kittila and Kevitsa. An optimisation algorithm was constructed to form a linear combination of reference spectra which best represent the measured spectrum from an ore sample. The reference spectra were collected from a public source. It was found that solving for an optimal summation of reference spectra can be a …

Exact extension of the DIRECT algorithm to multiple objectives

2019

The direct algorithm has been recognized as an efficient global optimization method which has few requirements of regularity and has proven to be globally convergent in general cases. direct has been an inspiration or has been used as a component for many multiobjective optimization algorithms. We propose an exact and as genuine as possible extension of the direct method for multiple objectives, providing a proof of global convergence (i.e., a guarantee that in an infinite time the algorithm becomes everywhere dense). We test the efficiency of the algorithm on a nonlinear and nonconvex vector function. peerReviewed

Energy Efficient Optimization for Wireless Virtualized Small Cell Networks With Large-Scale Multiple Antenna

2017

Wireless network virtualization is envisioned as a promising framework to provide efficient and customized services for next-generation wireless networks. In wireless virtualized networks (WVNs), limited radio resources are shared among different services providers for providing services to different users with heterogeneous demands. In this paper, we propose a resource allocation scheme for an orthogonal frequency division multiplexing-based WVN, where one small cell base station equipped with a large number of antennas serves the users with different service requirements. In particular, with the objective to obtain the energy efficiency in the uplink, a joint power, subcarrier, and antenn…

An IPMSM torque/weight and torque/moment of inertia ratio optimization

2014

In this paper, a torque/weight and torque/moment of inertia ratio optimization procedure for interior permanent magnet syncronous motors (IPMSMs) is presented. More in detail, a performance comparison between several IPMSM rotor structures has been carried out in order to determine the optimum geometry that can maximize the torque/weight and torque/moment of inertia ratios. A commercial motor, with known electrical and mechanical characteristics, has been taken as reference. Its rotor structure has been modified several times, obtaining different rotor geometries and, therefore, many IPMSM models with different electrical and mechanical characteristics. The finite element method (FEM) analy…