115 research outputs found
Towards an efficient haptic rendering using data-driven modeling
This thesis focuses on the optimisation of haptic rendering of interactions with deformable models. The research demonstrated that data-driven techniques can produce a real-time, accurate and complex simulation experience. Applications include, but not limited to, virtual training, rapid prototyping, virtual presence, and entertainment
Experimental Investigation on the Flexural Capacity of Reinforced Concrete Beams with Treated Wastewater and Recycled Concrete Aggregates
Eco-friendly concrete is the most recommended sustainable option to reduce the excessive diminution of concrete natural resources and the high generation of greenhouse gas emissions. Therefore, the present study explores the feasibility of employing treated wastewater (TWW), recycled concrete aggregates (RCA), and fly ash (FA) in concrete mixes. A total of 4 reinforced concrete (RC) beams were investigated under 4-point bending setup with three parameters investigated; namely, mixing water (fresh water and TWW), coarse aggregates (gabbro and RCA), and cementitious binders (cement and FA). The experimental results revealed that the beams' ductility was decreased by 9% and 16% with TWW and RCA, respectively. Moreover, the flexural performance of the TWW-RC beams was decreased by 14%, whereas RCA-RC beams showed comparable flexural strength to its counterpart with natural aggregates. In addition, the utilization of FA at a 20% replacement ratio enhanced the flexural strength by 5% to 7%
Combined effects of treated domestic wastewater, fly ash, and calcium nitrite toward concrete sustainability
The drastic increase in freshwater and ordinary Portland cement (OPC) consumption poses severe environmental and economic challenges worldwide. This study; therefore, explores the mechanical and durability properties of concrete incorporating treated domestic wastewater (TWW), class F fly ash (FA), and calcium nitrite-based corrosion inhibitor (CN). OPC paste and mortar with TWW were first prepared and compared with the permissible limits specified in ASTM C1602/C1602M ? 18 provisions. After that, ten concrete mixes were prepared with different ratios of TWW (0%, 25%, 50%, and 100%), FA (0%, 20%, and 35%), and CN (0% and 3%) and tested for fresh slump and density, compressive and flexural strengths, electrical resistivity, porosity, and chloride permeability. All concrete specimens were cured with fresh water. Concrete hardened properties were tested at 7, 28, and 90 days. Test results revealed that TWW slightly decreased concrete compressive and flexural strengths by 5%-12%, whereas it dramatically increased the porosity and chloride permeability by about 40%. It was also shown that the addition of FA significantly decreased the chloride permeability of TWW concrete by 55%-71%. The optimum FA replacement ratio was observed at 20 wt%. The addition of CN was shown to deteriorate the strength and durability properties of freshwater concrete by 10%-39%. However, combining TWW and CN has improved concrete resistivity, porosity, chloride permeability by 32%, 28%, and 32%, respectively. The optimum concrete properties were obtained using 20 wt% FA and 0% CN. The obtained results were analytically supported by scanning electron microscopy (SEM), energy-dispersive X-ray microanalysis (EDX), and X-ray diffraction (XRD) tests. Moreover, Pearson correlation and linear regressions were performed on the experimental data.This publication was made possible by GSRA grant GSRA6-1-0509-19022 from the Qatar National Research Fund (QNRF, a member of Qatar Foundation ). The authors would like also to thank the Central Laboratories Unit (CLU) at Qatar University for the scanning electron microscopy and energy-dispersive X-ray microanalysis images. Also, the financial support from Qatar University through grant no. QUST-1-CENG-2021-20 is acknowledged. Open Access funding provided by the Qatar National Library. The findings achieved herein are solely the responsibility of the authors.Scopu
Kinect crowd interaction
Most of the state-of-the-art commercial simulation software mainly focuses on providing realistic animations and convincing artificial intelligence to avatars in the scenario. However, works on how to trigger the events and avatar reactions in the scenario in a natural and intuitive way are less noticed and developed. Typical events are usually triggered by predefined timestamps. Once the events are set, there is no easy way to interactively generate new events while the scene is running and therefore difficult to dynamically affect the avatar reactions. Based on this situation, we propose a framework to use human gesture as input to trigger events within a DI-Guy simulation scenario in real-time, which could greatly help users to control events and avatar reactions in the scenario. By implementing such a framework, we will be able to identify user’s intentions interactively and ensure that the avatars make corresponding reactions
Strategies for improving training impact, retention and transfer in Saudi Arabian border guards
Comparing in vitro maturation rates in buffalo and cattle oocytes and evaluating the effect of cAMP modulators on maturation and subsequent developmental competence
Objective: The purpose of this research was to compare the kinetics and meiotic advancement of cattle and buffalo oocytes, as well as to see how cAMP modulators affected the meiotic progression status of cattle and buffalo oocytes during the oocyte collection process.Design: comparing maturation stages times in buffalo and cattle oocytes. Cattle and buffalo oocytes were collected, separated into two groups (standard IVM and extended IVM), and cultivated for five hours in 5% CO2 at 39°C. The sample times for extended IVM are 8, 15, 18, 22, 24, and 30 hours. The nuclear status of each oocyte was assessed to determine how far it had matured at each time sample. Then after, study the effect of cAMP modulators on maturation rates of cattle and buffalo oocytes.Procedures: Standard IVM samples were taken at different maturation times, commencing at 8 h and ending at 24 h, while extended IVM samples were taken at 30 h. COCs were placed in a 15-mL sterile centrifuge tube with a warmed 3 percent sodium citrate solution and vortexed at maximum speed for 4 to 8 minutes as needed to remove all cumulus cells before being placed in a warm water bath at 39°C for 5 minutes. After that, the oocytes were mounted on a slide and placed in Coplin jars with a 3:1 methanol/acetic acid solution.Results: At any stage of sampling, the percentage of oocytes arrested at the GV stage did not differ significantly between cattle and buffalo oocytes. Furthermore, there was no significant difference between cattle and buffalo oocytes in terms of the percentage of oocytes that reached the MI stage. Moreover, the percentage of oocytes arrested at the GV stage did not differ substantially between cattle and buffalo oocytes when maturation was extended using cAMP modulators at all stages of sampling. Conclusion and clinical relevance: Modulating cAMP during oocyte maturation can change oocyte kinetics and increase developmental competence by boosting fertilization, cleavage, and morula rates. Furthermore, there is no significant differences in maturation rates between buffalo and cattle oocytes
Effect of U-turns and heavy vehicles on the saturation flow rates of left-turn lanes at signalized intersections
© 2020 by the authors. The Saturation Flow Rate (SFR) is a primary measure that can be used when estimating intersection capacity. Further, the efficiency of signal control parameters also depends on the accuracy of assumed SFR values. Driver behavior, type of movement, vehicle type, intersection layout, and other factors may have a significant impact on the saturation flow rate. Thus, it is expected that driving environments that have heterogeneous driver populationswith different driving habits and culturesmay have different SFRs. In practice, the proposed SFRs based on US standards (Highway Capacity Manual, 2016) have been adopted in the State of Qatar without validation or calibration to consider the local road environment and the characteristics of the driving population. This study aims to empirically analyze the saturation flow rates for exclusive left-turn lanes and shared left-and U-turn lanes at two signalized intersections in Doha city, while considering the effects of heavy vehicles and U-turn maneuvers. Empirical observations revealed that the average base SFR, i.e., when the influences from heavy vehicles and U-turns were excluded, could vary approximately from 1800 vehicles per hour per lane (vphpl) to 2100 vphpl for exclusive left-turning lanes and approximately from 1800 vphpl to 1900 vphpl for shared left-and U-turning lanes. Furthermore, this study proposed different adjustment factors for heavy vehicle and U-turn percentages which can be applied in practice in designing signalized intersections, particularly in the State of Qatar
Data-based dynamic haptic interaction model with deformable 3D objects
The data-based modeling of the haptic interaction simulation is a growing trend in research. These techniques offer a quick alternative to parametric modeling of the simulation. So far, most of the use of the data-based techniques was applied to static simulations. This paper introduces how to use data-based model in dynamic simulations. This ensures realistic behavior and produce results that are very close to parametric modeling. The results show that a quick and accurate response can be achieved using the proposed methods
Combination of probiotics and coccidiosis vaccine enhances protection against an challenge
Référence bibliographique : Rol, 103004Appartient à l’ensemble documentaire : Pho20RolImage de press
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