http://ktisis.cut.ac.cy/handle/10488/4912 Search the Channel search http://ktisis.cut.ac.cy/simple-search http://ktisis.cut.ac.cy/handle/10488/7559 Title: Developments in structural system reliability assessments of fixed steel offshore platforms<br/><br/>Authors: Onoufriou, Toula; Forbes, V.J<br/><br/>Abstract: In recent years there have been significant developments in the area of system reliability assessments which are becoming increasingly important given the framework of the ‘goal setting’ regime and other changes that are taking place within the offshore industry. The objective of this paper is to review and critically examine recent developments in system reliability methods for fixed steel offshore platforms specifically and identify areas that need to be examined further to maximise the benefits from the use of these techniques.The paper examines the range of proposed methods for system reliability assessment of fixed steel offshore structures under extreme environmental loading. The associated characteristics of the various methods are examined and the paper concentrates in particular on the treatment of the resistance. The various system effects including both deterministic and probabilistic effects and their relative contribution to the overall system reliability are addressed. Key issues such as the modelling uncertainties and sensitivities, validation and benchmarking of the proposed methods are also examined. The study also highlights a number of technical and philosophical issues which need to be addressed to increase the benefits from system reliability applications in design and re-assessment of fixed platforms. http://ktisis.cut.ac.cy/handle/10488/7350 Title: Performance updating of concrete bridges using proactive health monitoring methods<br/><br/>Authors: Onoufriou, Toula; Rafiq, M.I.; Chryssanthopoulos, M.K.<br/><br/>Abstract: Uncertainties associated with modelling of deteriorating bridges strongly affect management decisions, such as inspection, maintenance and repair actions. These uncertainties can be reduced by the effective use of health monitoring systems, through which information regarding in situ performance can be incorporated in the management of bridges. The objectives of this paper are twofold; first, an improved chloride induced deterioration model for concrete bridges is proposed that can quantify degradation in performance soon after chlorides are deposited on the bridge, rather than when initiation of corrosion at the reinforcement level takes place. As a result, the implications of introducing proactive health monitoring can be assessed using probabilistic durability criteria. Thus, the second objective of the paper is to present a methodology for performance updating of deteriorating concrete bridges fitted with a proactive health monitoring system. This methodology is illustrated via a simple example of a typical bridge element, such as a beam or a part of a slab. The results highlight the benefits from introducing 'smart' technology in managing bridges subject to deterioration, and quantify the reduction in uncertainties and their subsequent effect on predictions of future bridge performance. http://ktisis.cut.ac.cy/handle/10488/7214 Title: Asymmetries in peer interaction: The effect of social representations of gender and knowledge asymmetry on children's cognitive development<br/><br/>Authors: Zapiti, Anna; Psaltis, C.<br/><br/>Abstract: This study examines the role of social representations of gender and knowledge as sources of asymmetry on the features of children's interactions as well as on their cognitive development. The research was carried through an innovative pre-test, first interaction, second interaction, post-test design. One hundred fifty-nine children of the same age (6.5-7.5 years old) but of different levels of knowledge of a spatial-transformation task collaborated in same-sex and opposite-sex dyads to find a joint solution. In the first interaction, a child less developmentally advanced (NC) had to work with a child more developmentally advanced (TC), whereas in the second interaction of the same gender composition, the same NC had to work with a fresh NC. Cognitive progress was assessed using pre-test to post-test gains. The results revealed that the gender composition of the pairs and knowledge asymmetry influence not only the behavioral patterns and strategies that each partner employs in the interaction but also the cognitive outcomes of the children. These findings shed more light to the process through which socio-cognitive conflict gets resolved, which was considered until now a "black box". http://ktisis.cut.ac.cy/handle/10488/7192 Title: Improving subspace learning for facial expression recognition using person dependent and geometrically enriched training sets<br/><br/>Authors: Maronidis, Anastasios G.; Bolis, D.; Tefas, A.; Pitas, I.<br/><br/>Abstract: In this paper, the robustness of appearance-based subspace learning techniques in geometrical transformations of the images is explored. A number of such techniques are presented and tested using four facial expression databases. A strong correlation between the recognition accuracy and the image registration error has been observed. Although it is common-knowledge that appearance-based methods are sensitive to image registration errors, there is no systematic experiment reported in the literature. As a result of these experiments, the training set enrichment with translated, scaled and rotated images is proposed for confronting the low robustness of these techniques in facial expression recognition. Moreover, person dependent training is proven to be much more accurate for facial expression recognition than generic learning.