Search results for "membership"
showing 10 items of 75 documents
Marginal analysis for the fuzzy p-median problem
2008
The solutions to the fuzzy p-median problem make it possible to leave part of the demand uncovered in order to obtain significant reductions in costs. Moreover, the fuzzy formulation provides the decision-maker with many flexible solutions that he or she may prefer to the classical crisp solution. We introduce some marginal analysis techniques to study how solutions depend on membership functions. Taking into account the internal structure of the problem, we propose a practical criterion to fix the tolerances for the uncovered demand, which happens to be the most sensitive aspect of the fuzzy p-median.
Optimization under Uncertainty and Linear Semi-Infinite Programming: A Survey
2001
This paper deals with the relationship between semi-infinite linear programming and decision making under uncertainty in imprecise environments. Actually, we have reviewed several set-inclusive constrained models and some fuzzy programming problems in order to see if they can be solved by means of a linear semi-infinite program. Finally, we present some numerical examples obtained by using a primal semi-infinite programming method.
Relaxed Stability and Performance LMI Conditions for Takagi-Sugeno Fuzzy Systems With Polynomial Constraints on Membership Function Shapes
2008
Most linear matrix inequality (LMI) fuzzy control results in literature are valid for any membership function, i.e., independent of the actual membership shape. Hence, they are conservative (with respect to other nonlinear control approaches) when specific knowledge of the shapes is available. This paper presents relaxed LMI conditions for fuzzy control that incorporate such shape information in the form of polynomial constraints, generalizing previous works by the authors. Interesting particular cases are overlap (product) bounds and ellipsoidal regions. Numerical examples illustrate the achieved improvements, as well as the possibilities of solving some multiobjective problems. The result…
Young Scottish National Party (SNP) Members’ National Identity and Party Membership
2021
Scotland’s future in the United Kingdom seems to be uncertain. Even though a majority of Scottish people voted to remain in the UK in 2014, the EU referendum two years later fuelled the independence movement in Scotland. Scholars show that the Scottish independence referendum encouraged people to join political parties, particularly the Scottish National Party. This work focuses on young people. Party membership scholars agree that they are underrepresented in parties. Given that the SNP seem to be rather successful in appealing to young people, this thesis explores SNP youth membership and the reasons why young Scots make the decision to join the party. It shows that Scottish independence …
Membership duration in a Spanish union : a survival analysis
2013
Background of INCASI Project H2020-MSCA-RISE-2015 GA 691004. WP1: Compilation This article presents an analysis of the characteristics that are associated with union membership duration using data from the membership registers of the largest Spanish trade union: Comisiones Obreras (CCOO, Workers' Commissions). Making use of survival analysis techniques, the results indicate that the shortest membership durations and the highest risks of leaving are associated with workers with poor employment conditions, mainly youth and foreigners, as well as those in firms, economic sectors, and territories where the union has a rather weak presence. As workers in these situations represent the majority o…
A longitudinal person-centred view on perceived employability : The role of job insecurity
2013
The primary aim of the present 1-year longitudinal study among university employees (N = 1314) was to investigate individual development of perceived employability (PE) by utilizing a person-centred approach. Thus, we identified latent classes of PE across 1 year based on growth mixture modelling. In addition, the latent classes were characterized by perceived job insecurity and the type of employment contract and its changes over the 1-year time period. The results showed four latent classes of PE that differed in the level and the direction of mean-level changes over time. These latent classes were: (1) stable relatively high PE (n = 641); (2) unstable decreasing PE (n = 45); (3) unstable…
Fuzzy Mathematical Programming for Portfolio Management
2000
The classical portfolio selection problem was formulated by Markowitz in the 1950s as a quadratic programming problem in which the risk variance is minimized. Since then, many other models have been considered and their associated mathematical programming formulations can be viewed as dynamic, stochastic or static decision problems. In our opinion, the model formulation depends essentially on two factors: the data nature and the treatment given to the risk and return goals. In this communication, we consider several approaches to deal with the data uncertainty for different classical formulations of the portfolio problem. We make use of duality theory and fuzzy programming techniques to ana…
A Fuzzy Adaptive Controller for an Ambient Intelligence Scenario
2014
The definition of effective energy saving strategies capable of satisfying users’ requirements for environmental wellness is a complex task that requires the definition of well-tuned optimization algorithms. Sensory information depends on the environments observed, hence the model adopted to describe it should be adaptive and dynamic. This chapter presents a methodology for the tuning of a fuzzy controller capable of minimizing energy consumption while maximizing the users comfort in an Ambient Intelligence Scenario. A meta-heuristic search algorithm produces different sets of fuzzy rules depending on the needs of the system. An ontology has been developed to describe the configurations of …
Young children in day and night care : negotiating and constructing belonging during daily arrivals
2016
The paper aims at understanding the processes related to young children's belonging during daily arrivals at day and night care. Two aspects of a child's belonging are considered: membership and sense of belonging. Data were gathered by ethnographic observation of 8 children aged from 20 to 36 months in two Finnish day care centres offering day and night care. Arrival episodes taking place at different times of day were analysed qualitatively based on the children's actions and expressions. During these episodes, the children negotiated and constructed their belonging by interacting with adults, peers and material objects. These interactions took place within varying social and material sur…
La dinámica afiliativa sindical y las trayectorias de sus miembros
2013
Este texto recoge los primeros resultados del Proyecto trianual de Investigación Fundamental no orientada Ref. CSO2010-17962, aprobado por el Ministerio de Ciencia e Innovación (Convocatoria 2010) y del que soy investigadora principal. Dicho Proyecto de I+D, que lleva por título La construcción política del evangelismo gitano: Iglesias, federaciones y nuevos actores políticos, cuenta con la participación formal de la Dra. Teresa San Román Espinosa, catedrática de Antropología Social de la Universidad Autónoma de Barcelona Background of INCASI Project H2020-MSCA-RISE-2015 GA 691004. WP1: Compilation Este texto analiza la dinámica afiliativa de altas y bajas de los sindicatos españoles a part…