196 research outputs found
Evaluating the Effects of High Penetration of Roof-Top Wind Turbines on Secondary Distribution Circuits
Full-Scale Shaking Table Tests on Deficient Rc Buildings Strengthened With FRP Composites
The paper discusses the results from experimental programmes including full-scale shaking table tests on two deficient one-span two-storey RC frame buildings strengthened with Carbon Fibre Reinforced Polymer (CFRP) composites. The tests were performed at one of the world class shaking table testing facility, the AZALEE shake table at the Commissariat à l’Énergie Atomique (CEA), Laboratory in Saclay, France, as part of two European (EU) funded research projects (EU ECOLEADER project and EU FP7 SERIES/ BANDIT project). The aim of these experimental programmes was to investigate the effectiveness of externally bonded CFRP reinforcement in improving the seismic behaviour of deficiently designed RC buildings. To simulate typical substandard design, the reinforcement of beam-column joints and columns of the two full-scale frames had inadequate detailing. In both projects, initial shaking table tests were carried out to assess the seismic behaviour of the bare frame buildings. Columns and joints were subsequently repaired and strengthened using CFRP composite material for the ECOLEADER frame, and a strengthening solution consisting of CFRP composite material and Post-Tensioned Metal Straps for the BANDIT frame. The frames were then subjected to incremental seismic excitations to assess the effectiveness of the strengthening solutions in improving the global and local frame performance. Whilst the original bare frames were significantly damaged at a peak ground acceleration (PGA) of 0.15-0.20g, the strengthened frames resisted severe shaking table tests up to PGA=0.50-0.60g without failure. Moreover, the strengthening interventions enhanced the interstorey drift ratio capacity and proved to be very effective in addressing the seismic deficiencies of substandard buildings
Cyber security incident handling, warning and response system for the european critical information infrastructures (cyberSANE)
This paper aims to enhance the security and resilience of Critical
Information Infrastructures (CIIs) by providing a dynamic collaborative,
warning and response system (CyberSANE system) supporting and guiding security
officers and operators (e.g. Incident Response professionals) to recognize,
identify, dynamically analyse, forecast, treat and respond to their threats and
risks and handle their daily cyber incidents. The proposed solution provides a
first of a kind approach for handling cyber security incidents in the digital
environments with highly interconnected, complex and diverse nature
Analysis and tests of TF magnet insulation samples for the JET upgrade to 4 tesla
The JET Toroidal Field (TF) coils were originally designed for operation at 3.4 tesla. In order to upgrade the field to 4 tesla and thus improve the performance of the JET machine, new mechanical tests and analysis were carried out on the insulation of TF coil samples. They are aimed at investigating the mechanical properties and the status of the insulation in order to set allowable stresses and force limits. In particular since the shear stress in the insulation is strongly affected by the shear modulus of elasticity G, it is important to measure this parameter. A method for the measurement of G in glass-resin fibres, the V-notched beam method (Iosipescu method) , was applied. The particular shape of the rectangular Iosipescu V- notched sample and the particular modality of force application produce pure shear stress for a reliable measurement of the G value and of the shear strength of the insulation. The effect of temperature on these mechanical properties was also investigated. Results show higher average shear strength with lower scatter compared with previous tests on conventional rectangular samples, thus confirming the reliability of the method. Micrographic analysis of the insulation and comparison between the straight and curved regions of the magnet, where the highest stress occurs, confirm the good quality of the impregnation of the coil. Glass-resin content, void content, micros and TG measurements have been performed on different samples and correlation between the different properties of the insulation investigated. Moreover fatigue tests at different temperatures were performed and data analyzed with the cumulative damage technique, which allows for an extrapolation of the fatigue curve with less samples than the standard method. (6 refs)
Shaking Table Tests on RC Retrofitted Frame with FRP
This paper describes the experimental work undertaken on FRP seismic strengthening of a RC structure as part of the “Ecoleader” European program. Shaking table tests were performed on a one-bay, 2 storey, full-scale spatial RC-frame (4 m x 4 m, 6.6 m high, 30 t mass) at CEA Saclay on the AZALEE shaking table. Two further papers in this conference will describe the analytical work relating to the tests. The main objective of the program was to assess different strengthening strategies and techniques on a seismically under-designed R/C frame structure, in order to develop simple and rational techniques for use in FRP-strengthening of R/C structural elements (i.e., beams, columns and joints) and quantify their effectiveness through design equations. The original frame was shaken until severe damage was achieved and a sway mechanism was developed. It was subsequently strengthened with Carbon FRP aiming to change the collapse mechanism. The strengthening procedure proved to be amazingly successful and the frame resisted shaking up to the limits possible by the capacity of the shaking table
Embryo with XYY syndrome presenting with clubfoot: a case report
Talipes equinovarus (clubfoot) is a skeletal anomaly of the embryo’s legs, with a frequency of 1-3:1000 living born babies. It may occur as an independent anomaly, or as part of a syndrome with concomitant chromosomal abnormalities
Experimental investigation of RC full scale frame strengthened at the joints and columns with fibre reinforced polymers
This paper presents the strengthening procedure of a two storey RC full-scale structure tested on a shaking table. The bare frame, designed by using old European regulations, was subjected to a series of earthquakes until severe damage was caused in the joints. The strengthening strategy aimed to apply a minimal/optimal amount of CFRP sheets onto joints and columns so as to enhance their shear and flexural capacity and to transfer the plastic hinges from columns to beams. Construction details are given to show how joints and columns were strengthened and how the CFRP sheets were anchored on the external and internal joint faces. Two different strengthening methods using orthotropic reinforcement were examined. Some of the experimental results are shown focusing on the two principal natural frequencies and maximum absolute displacements of all floors for both bare and retrofitted frame. The behaviour of the building was successfully changed from the strong beam-weak column frame to a more ductile frame as the plastic hinges were transferred from the columns to the beams
Mechanical properties of SFRC using blended manufactured and recycled tyre steel fibres
This paper investigates the mechanical properties of 10 steel fibre reinforced concrete (SFRC) mixes at fibre dosages of 30, 35 and 45 kg/m3. Manufactured Steel Fibres (MSF) are used on their own, or blended with sorted steel fibres recycled from end-of-life tyres (RTSF). To characterise the flexural behaviour of the mixes, two flexural test methods, BS EN 14651:2005 3-point notched prism tests and ASTM C1550-05 centrally loaded round panel tests are employed. A strong correlation is found in the flexural behaviour of the SFRC prism and round panel specimens, with corresponding conversion equations proposed. The mechanical properties of hybrid mixes using RTSF vary depending on dosages, but are comparable with those of MSF-only mixes at the same fibre dosage. A positive synergetic effect is derived from hybrid mixes containing 10 kg/m3 of RTSF
Spatial-spectral flexible optical networking:enabling switching solutions for a simplified and efficient SDM network platform
The traffic carried by core optical networks grows at a steady but remarkable pace of 30-40% year-over-year. Optical transmissions and networking advancements continue to satisfy the traffic requirements by delivering the content over the network infrastructure in a cost and energy efficient manner. Such core optical networks serve the information traffic demands in a dynamic way, in response to requirements for shifting of traffics demands, both temporally (day/night) and spatially (business district/residential). However as we are approaching fundamental spectral efficiency limits of singlemode fibers, the scientific community is pursuing recently the development of an innovative, all-optical network architecture introducing the spatial degree of freedom when designing/operating future transport networks. Spacedivision- multiplexing through the use of bundled single mode fibers, and/or multi-core fibers and/or few-mode fibers can offer up to 100-fold capacity increase in future optical networks. The EU INSPACE project is working on the development of a complete spatial-spectral flexible optical networking solution, offering the network ultra-high capacity, flexibility and energy efficiency required to meet the challenges of delivering exponentially growing traffic demands in the internet over the next twenty years. In this paper we will present the motivation and main research activities of the INSPACE consortium towards the realization of the overall project solution
Designing Playful Games and Applications to Support Science Centers Learning Activities
In recent years there has been a renewed interest on science, technology, engineering, and mathematics (STEM) education. Following this interest, science centers\u27 staff started providing technology enhanced informal STEM education experiences. The use of well-designed mobile and ubiquitous forms of technology to enrich informal STEM education activities is an essential success factor. The goal of our research is to investigate how technology applications can be better used and developed for taking full advantage of the opportunities and challenges they provide for students learning about STEM concepts. In our approach, we have conducted a series of interviews with experts from science center curating and outdoor learning activities development, with the final goal of exploring and improving current learning environments and practices. This paper presents the development of set of design considerations for the development of STEM games and applications of young students. An initial set of best practices was first developed through semi-structures interviews with experts; and afterwards, by employing content analysis, a revised set of considerations was obtained. These results are useful for STEM education teachers, curriculum designers, curators and developers for K-12 education environments
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