19 research outputs found
كتاب الدر المنتخب ليوحنا فم الذهب
No full textThis text included excerpts of the sayings of Saint John Chrysostom, translated from Greek to Arabic, and thirty-four spiritual essays. The manuscript was composed by Butrus Girgis, and it was handwritten by Yusuf Hanna in 1843. It includes decca, a typical form of Coptic Orthodox illustration. Saint John Chrysostom, the author, served as the patriarch of Constantinople, a position forced upon him in 389 C.E. Born in Antioch circa 347 C.E., he devoted several years to monastic life, spending part of this time as a hermit. Chrysostom means "golden-mouthed."The Iryan Moftah Coptic Language and Religion Manuscript and Book Collection was acquired in 2003 thanks to Laurence Moftah who generously arranged for its transfer to the Rare Books and Special Collection Library in support of the preservation of Coptic heritage and the Coptic studies program at the American University in Cairo. The manuscripts were originally digitized and described by Father Maximous El-Antony with the aid of the Rare Books and Special Collections Library in 2010
Fracture Strength of Acrylic Resin Reinforced with Glass Fibers in Simulated Implant-Supported Overdenture Abutments
No full textObjective: To evaluate the effect of glass fibers on acrylic resin fracture strength in simulated implant-supported overdenture (IOD) abutments.
Methods: A model was designed to simulate the clinical situation of an IDO (50 12 1.5 mm). Thirty models were divided into three equal groups: ten models not supported with glass fibers (control group), ten models with one layer of glass fibers (experimental group I) and ten models with two layers of glass fiber (experimental group II). All models were exposed to a three-point bending test, and fracture loads were analyzed using a one-way analysis of variance (ANOVA) followed by Bonferroni post-hoc test.
Results: IOD models reinforced with two layers of glass fibers (experimental group II) showed a mean ultimate load at fracture of 48.69 ± 3.71 Newton (N) compared to mean loads of 32.78 ± 2.41 N and 24.42 ± 2.73 N for the models reinforced with one layer (experimental group I) and non-reinforced with glass fibers (control group), respectively. ANOVA showed a statistically significant difference between the three groups regarding the mean ultimate load at fracture, and Bonferroni post-hoc test showed statistically significant differences between both experimental groups and the control group as well as between experimental group I and experimental group II.
Conclusions: The fracture strength of IDO abutments increases significantly by the addition of acrylic resin pre-impregnated with glass fibers, even when the thickness of acrylic is thin
Design, Fabrication and Calibration of Compliant, Multi-Axis, Fiber-Optic Force/Torque Sensors for Biomechanical Measurements
No full textThis thesis presents the design, fabrication and characterization of various prototypes of multi-axis, compliant force and torque sensors based on fiber-optic sensing technology, the novel calibration methodologies and the experimental results. A compliant 3-axis, intensity modulated-based, fiber-optic force sensor that simultaneously measures normal and shear forces was designed, prototyped and successfully calibrated. A nonlinear Hammerstein-Weiner model (NLHW) was able to characterize the linear and nonlinear behaviour of this prototype. The optimized results have shown a reduction of over 40% in the Root Mean Square Errors (RMSE) in comparison with the linear estimation models. For biomechanical applications such as ground reaction force and gait measurements, the sensor must be able to measure the complete degree of freedom of any force or torque applied at a certain point. Therefore, a wearable compliant 6-axis force and torque sensor was developed and prototyped. It combines two different force sensing technologies: the 3-axis fiber-optic based force sensor and a pressure sensor matrix. The sensor was capable of accurately measuring the full ground reaction force and moment in real-time with minimal gait disturbance. To enhance the durability, avoid the necessary multi-stage conditioning circuits and their resulting extra electronic components, a 6-axis force and torque sensor that is fully optical has been developed and characterized. The sensor is cost-effective, lightweight and flexible with a large force and torque measurement range suitable for biomechanics and rehabilitation systems. A novel calibration methodology which splits the calibration procedure into two estimation models that work simultaneously as a single calibration system named Least Squares Decision Trees (LSDT). Using LSDT, the estimation speed increased by 55.17% and the RMSE reduced to 0.53%. To improve sensor portability, further reduce size and eliminate electromagnetic interference effects as well as enhance sensor biocompatibility, a non-conductive, electrically passive, fiber Bragg grating (FBG) based normal and shear force sensing elements were designed, fabricated and calibrated. The sensing elements are small size, lightweight and compliant. The results achieved from the proposed calibration method have revealed an improvement from an R-squared value of 93% to 100% when compared to a data obtained using a linear least squares method
Do Oil Price Shocks and COVID-19 Lead to Policy Uncertainty?
No full textThis study examines the asymmetric effects of the structural oil price shocks and COVID-19 pandemic on four uncertainty indexes. The author used the SVAR approach for the period 31-Dec-2019 to 28-Jun-2020. The results indicate that the effects are asymmetric of oil price shocks. The author also finds that COVID-19 shocks lead to positive responses to the economic policy uncertainty index. In addition, oil prices (their shocks) have a negative impact on the four indicators of uncertainty. Consequently, governments should actively take effective measures to prevent crude oil prices from shocking and maintain stable economic policies
Depth-based human activity recognition: A comparative perspective study on feature extraction
No full textDepth Maps-based Human Activity Recognition is the process of categorizing depth sequences with a particular activity. In this problem, some applications represent robust solutions in domains such as surveillance system, computer vision applications, and video retrieval systems. The task is challenging due to variations inside one class and distinguishes between activities of various classes and video recording settings. In this study, we introduce a detailed study of current advances in the depth maps-based image representations and feature extraction process. Moreover, we discuss the state of art datasets and subsequent classification procedure. Also, a comparative study of some of the more popular depth-map approaches has provided in greater detail. The proposed methods are evaluated on three depth-based datasets “MSR Action 3D”, “MSR Hand Gesture”, and “MSR Daily Activity 3D”. Experimental results achieved 100%, 95.83%, and 96.55% respectively. While combining depth and color features on “RGBD-HuDaAct” Dataset, achieved 89.1%
Depth-based human activity recognition: A comparative perspective study on feature extraction
No full textStatistical HOG on Multi-temporal Depth Motion Maps Approach for Human Action Recognition
No full textFracture Strength of Acrylic Resin Reinforced with Glass Fibers in Simulated Implant-Supported Overdenture Abutments
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A 1.5-year randomized controlled trial comparing standard-sized implants and two diameters of mini-implants immediately loaded by mandibular overdenture: radiographic outcomes, short-term survival, and success rate
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