Fault reconstruction using a LPV sliding mode observer for a class of LPV systems

This paper proposes a new sliding mode observer for fault reconstruction, applicable for a class of linear parameter varying (LPV) systems. Observer schemes for actuator and sensor fault reconstruction are presented. For the actuator fault reconstruction scheme, a virtual system comprising the system matrix and a fixed input distribution matrix is used for the design of the observer. The fixed input distribution matrix is instrumental in simplifying the synthesis procedure to create the observer gains to ensure a stable closed-loop reduced order sliding motion. The ‘output error injection signals’ from the observer are used as the basis for reconstructing the fault signals. For the sensor fault observer design, augmenting the LPV system with a filtered version of the faulty measurements allows the sensor fault reconstruction problem to be posed as an actuator fault reconstruction scenario. Simulation tests based on a high-fidelity nonlinear model of a transport aircraft have been used to demonstrate the proposed actuator and sensor FDI schemes. The simulation results show their efficacy.     

Generation of virtual models of cultural heritage

Different techniques and tools currently exist to generate three-dimensional models of small elements, buildings and cities. Apart from being easier to interpret than two-dimensional drawings, these models facilitate data necessary for reconstruction projects, preservation or rehabilitation of the architectural or archaeological heritage. Traditional surveying only enables us to obtain discrete information of the characteristic lines that define each surface, edge, slope change etc. whereas work with massive capture techniques allows us to obtain continuous points of the surfaces. Photogrammetry or laser scanning combined with conventional photography provides information of the building in addition to its geometry. We carried out a review of the different techniques showing the advantages and disadvantages of each technique as well as the information that can be obtained by applying these techniques to the survey of the great Gate of Antioch in the town of Aleppo, declared a World Heritage Site by UNESCO in 1986, in Syria.     

Hirsch-type characteristics of the tail of distributions. The generalised h-index

In this paper a generalisation of the h-index and g-index is given on the basis of non-negative real-valued functionals defined on subspaces of the vector space generated by the ordered samples. Several Hirsch-type measures are defined and their basic properties are analysed. Empirical properties are illustrated using examples from the micro- and meso-level. Among these measures, the h-index proved the most, the arithmetic and geometric g-indices, the least robust measures. The μ-index and the harmonic g-index provide more balanced results and are still robust enough.     

Training and psychosocial patterns during the early development of Portuguese national team athletes

This study explored the early development of expert athletes compared to a group of athletes that did not achieve an expert level of performance despite being involved in youth events with their national squads. In particular, the activities, training patterns, and psychosocial influences that characterized their paths in competitive sports were examined. Male and female participants (N?=?42) from different sports were interviewed. Overall, athletes showed several commonalities. However, experts were selected to national squads later and also started thinking about investing in becoming elite athletes later. Non-experts revealed more parental pressure and less individual training with coaches.     

The Goals of a Voluntary Integration Program and the Problems of Access: A Closer Look at a Magnet School Application Brochure

The article incorporates a critical theoretical and methodological framework to study a large urban district's implementation of a court-ordered voluntary integration program through magnet school choice. Drawing on the interview data from parents and district staff, the author analyzes the data as they relate to the district's magnet school application brochure, Opportunities for Success, and how the application is designed to support the voluntary integration program. The article first presents a short historical grounding for the district's voluntary integration program and how it influences the choice options for parents. Next, it discusses how the district implemented and organized the voluntary integration program and produced the magnet school application text. It then introduces data on parents' interactions with the magnet school brochure and application. The article concludes with a discussion of what can be learned from studying the texts of a voluntary integration program, what it tells us about racial and class privilege and diverse families' access to magnet school programs, and how text analysis can help us see where, in the institutional processes of school choice, further resegregation is likely to take place.