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Wind power is considered an efficient alternative for production of electrical energy. One advantage that wind power offers compared to conventional ways of producing energy such as fossil energy and nuclear energy is the low emission of carbon dioxide "CO2" during production of electrical energy. In the last two decades extensive research and huge resources have been focused on production of wind power around the world. In the European Union (EU) the installation of wind power has an annual growth rate of over 11% from 3.2 GW in 2000 to 11.9 GW in 2012 [1] A wind power station consists of a tower with a turbine at the top. In the tower equipment used for transforming kinetic energy in the wind and turbine to electrical energy is placed. The cost for the tower is up to 27% of the total building cost. Building higher towers increases the output of wind power as the wind becomes more constant and the wind speed increases with the increase of the tower height. To make the tower hollow to create space for equipment, decrease weight and increase bending stiffness the walls should be as thin as possible. For such thin walled structures stability is one of the most dangerous failure cases, it leads to brittle failure. The tower needs to be stiff enough to prevent instability. In addition to this, it is important to use connections with high fatigue endurance, which is no considered in this analysis.One solution to reduce transportation costs is to manufacture the tower in sections, at least for onshore towers where the access is difficult. These towers can be made from using a lattice (truss) tower or a tubular tower made from steel. By using sections of high strength steel the towers will have more structural strength with more stability and lower cost as less material is used. As many of the tubular and lattice (truss) towers are made from thin elements it is important to study buckling. Therefore, a study of optimization by geometrical analysis and comparison with the actual standards is performed. Thin plates are often made from cold-formed steel with higher yield strength. The focus of this thesis is in the evaluation and the use of thin folded plates that can be combined to form polygonal cross-sections in towers for wind turbines. An initial numerical study of a folded plate with three different polygonal cross-sections was done using the Finite Element software ABAQUS [2]. The results are compared with EN 1993 part 1-3 [3] and EN 1993 part 1-5 [4]. The FEA showed local buckling as failure mode in all cases of the folded plates. The folded plates are designed to be used as section members for tubular and lattice (truss) towers. In the design for lattice towers the thin folded plates may be connected with gusset plates at different distances over the length of the plate to form a semi-closed cross-section column. For tubular towers the plates were designed to be connected by longitudinal connections to form a tube with a polygonal cross-section. The validity of the design rules given in EN 1993 part 1-3[3], EN 1993 part 1-5 [4], EN 1993 part 3-2 [5]and EN 1993 part 1-6 [6] were used. ; Godkänd; 2013; 20130404 (olgluc); Tillkännagivande licentiatseminarium 2013-05-31 Nedanstående person kommer att hålla licentiatseminarium för avläggande av teknologie licentiatexamen. Namn: Olga Garzon Ämne: Stålbyggnad/Steel Structures Uppsats: Resistance of Polygonal Cross-Sections - Application on Steel Towers for Wind Turbines Examinator:´Professor Milan Veljkovic, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Diskutant: Professor Carlos Alberto da Silva Rebelo, University of Coimbra, Portugal Tid: Onsdag den 19 juni 2013 kl 09.00 Plats: F1031, Luleå tekniska universitet

The aim of this paper is to analyze the role of small and informal groups of discussion can play in changing perceptions and biased beliefs about education policies and practices between different actors in the daily life of school. It outlines basic elements of an intervention model to improve the public and private image of educative system, through a pilot investigation in which the discussion of an informal group of educative actors on educational issues seems to facilitate the rethinking of these perceptions and positions. Two groups face different tasks. A group is an active participant in these discussions and the other performs an entertainment task. It is assumed that the first group changed their initial positions. To measure changes in both groups were asked to complete the Altemeyer authoritarianism Scale. Adapted from the source document.

The scientific investigation on the connections of psychology and politics doesn't appear in Spain until the second half of XX century. This field of the Spanish psychology between the 1970s and 1980s tried to become a new discipline and professional field. In 1990s the first Spanish journal of Political Psychology appeared. This article describes the significant trends of the Political Psychology in Spain in the last twenty years, based on the empirical analysis of the publications journals. The obtained results reveal a focus change in classic topics and the emergence of new political topics. It has diminished the interest for the institutional aspects of the democracies and it has increased the concern for the policy's civic vision. The Spanish political psychologists share characteristic fundamentally with the European and North American political psychologists, but they maintain styles characteristic of their origin places in what they worry as well as in the form in that they investigate. Adapted from the source document.

The thought of the Spanish judge who presided over the hearing involving the extradition of Augusto Pinochet from the UK to Spain during the late 1990s concerning human rights violations precedes an interview with same. Garzon discusses whether reconciliation can be achieved by prosecuting suspected human rights violators; states' obligation to prosecute suspected human rights violators; ideological implications of viewing genocide as a "living concept"; & failure to properly acknowledge victims in reconciliation & negotiation processes. Critical analysis of Garzon's thoughts is performed; eg, similarities between Garzon's thought & human rights discourse regarding the status of victims are noted. It is concluded that Garzon's aggressive prosecution of Pinochet provides new approaches for utilizing existing legal statutes to pursue suspected war criminals & human rights violators. J. W. Parker