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Numerous urban seismic vulnerability studies have recognized pounding as one of the main risks due to the restricted separation distance between neighboring structures. The pounding effects on the adjacent buildings could extend from slight non-structural to serious structural damage that could even head to a total collapse of buildings. Therefore, an assessment of the seismic pounding hazard to the adjacent buildings is superficial in future building code calibrations. Thus, this study targets are to draw useful recommendations and set up guidelines for potential pounding damage evaluation for code calibration through a numerical simulation approach for the evaluation of the pounding risks on adjacent buildings. A numerical simulation is formulated to estimate the seismic pounding effects on the seismic response demands of adjacent buildings for different design parameters that include: number of stories, separation distances; alignment configurations, and then compared with nominal model without pounding. Based on the obtained results, it has been concluded that the severity of the pounding effects depends on the dynamic characteristics of the adjacent buildings and the input excitation characteristics, and whether the building is exposed to one or two-sided impacts. Seismic pounding among adjacent buildings produces greater acceleration and shear force response demands at different story levels compared to the no pounding case response demands.

This study proposed Carbon fiber reinforced polymers (CFRP) as additional transverse reinforcement at the critical zones of concrete filled steel tubular (CFST). An experimental study consisted of five main sets of specimens representing the ends of columns, such as those merging in through beam-column connections, was conducted. Each main set of specimens investigated the behavior of the concrete core for a specific case of CFST or CFRP wrapped CFST (CFCFST), and each main set comprised three similar specimens to get more accurate results. All specimens were 160 mm external diameter and 320 mm height and had the same concrete grade. The thicknesses of the steel tubes used were 2 and 3mm. The numbers of (CFRP) layers used were one and two layers. The results showed that one and two CFRP outer layers added to CFST greatly improved the concrete compression. Response showed 29% and 54% increase in the concrete core compressive strength, respectively. The increase in the steel tube thickness from 2mm to 3 mm caused 20% increase in the concrete core compressive strength. A new analytical model with a sufficient accuracy was driven to predict the concrete core strength for both CFST and CFCFST cases.

There is a growing interest among architects to allow for a huge amount of daylighting inside office buildings as a way of achieving user’s visual comfort, however, this result in high energy consumption due to the high solar gain. Intelligent window techniques are considered a suitable solution for this issue due to their ability to change their main functional parameters based on the changing environmental situations and therefore contribute to reducing energy consumption. This paper reviews various types of glazing techniques and conducts a comparative study on 12 glazing techniques by measuring their performance on different facades of 1000 sq. m office building using Energy plus 8.6 simulation software (WWR 40%). Thus, guiding the selection of the best glazing technique for each facade. Studying the performance of each technique on single façade showed that the best glazing technique on the east and west directions were “Electrochromic glazing (EC) with low SHGC” which allowed for a reduction of 32.18% and 32.45% respectively. While the “EC glazing with medium SHGC” reached 31.91% reduction when applied on the south facade. On the other side, by applying each technique on the four facades together, the best cooling reduction of almost 49% was achieved by using “Triple with suspended Low-E film” glazing technique.

Seismic vulnerability assessments of buildings after several earthquakes have confirmed that the pounding could be one of the key threats. The pounding among series of neighbouring building structures throughout earthquakes exerts repeated strikes on each other that could be a reason for structural damages ranging from light damage to even collapse. So, the main objectives are to provide constructive suggestions for code calibration through a numerical simulation for the estimation of the pounding risks on series of neighbouring buildings separated by minimum code-specified separation. A numerical simulation and FE analysis are developed to estimate the influence of pounding on the seismic response demands of adjacent buildings. The collision effects on 3-, 6- and 12-stories adjacent buildings are studied for different separation distances and alignment configurations and compared with a nominal model without pounding considerations. Based on the obtained results, it is concluded that the seriousness of the impact effects is influenced by the vibration characteristics of the adjacent buildings, the input excitation characteristics and whether the building is exposed to one- or two-sided impacts. There are additional loads caused by the pounding which leads to additional shear forces and acceleration at different story levels that do not appear in the no-pounding case.

This paper introduces a sensing and stimulation system to transfer the electromyogram (EMG) signal from one limb to another, aiming to enable self-electro-physical therapy. The presented technique depends on sensing EMG signal from one limb muscle and, simultaneously, stimulating the corresponding muscle in the other limb by this signal. The technique has been implemented on a standalone cheap microcontroller. The sensing and stimulating circuits have been implemented using off-shelf components. The delivery of the stimulating signal has been done noninvasively through surface electrodes.

Through this paper we aim to measure a distance using an optical signal. The distance measurement is based on the time of the flight (TOF) method via correlation technique. A method of stretching the time scale is used to decrease the operating frequency. A proof of concept using Matlab results in a distance resolution less than 17mm. The algorithm is implemented on a standalone cheap digital signal controller and the measured results show high accuracy comparable to the simulated one. The optical transmitters and optical receivers are implemented using off shelf components.

Five reinforced concrete beams with rectangular cross section 120 x 300 mm and flexural reinforcement ratio of 0.0124 were cast and tested under three-point static loading. One beam was tested up to failure as control beam. The rest of the beams were loaded up to the inclined cracking load. Then the load was removed and the beams were repaired using steel fiber-reinforced self-consolidating concrete (SFRSCC) jacket with varied thicknesses and fiber contents. Then the repaired were retested up to failure. The fiber contents of 0.5, 0.75 and 0.75% by the volume of concrete as well as jacket thicknesses of 30 and 50 mm were considered for this study. The experimental results showed that the proposed technique enhanced the load capacity of the repaired beams by up to 121% with respect to the original specimen, and reduced the induced deflections and strains at the different stages of loading. Moreover, increasing fiber content with a fixed jacket thickness was found to be more effective than increasing the jacket thickness with the same fiber content.

This paper presents a Genetic Algorithm (GA)- based method to determine the location and size of DG sources in distribution systems using single DG placement algorithm for determining the locations at first. Then, the GA is utilized to determine the global sizes of DG sources which minimize single- or multi-objective function related to these systems. The influence of active- and reactive-power injection on the sizing and placement of DG sources is investigated. The predictions of the proposed method as regards the sizing and placement of DG sources are compared with those obtained before using particle swarm optimization at steady weather conditions.