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71.
Moez Kthiri Hassen Loukil Ahmed Ben Atitallah Patrice Kadionik Dominique Dallet Nouri Masmoudi 《Journal of Signal Processing Systems》2012,68(2):273-285
Motion estimation is a highly computational demanding operation during video compression process and significantly affects
the output quality of an encoded sequence. Special hardware architectures are required to achieve real-time compression performance.
Many fast search block matching motion estimation (BMME) algorithms have been developed in order to minimize search positions
and speed up computation but they do not take into account how they can be effectively implemented by hardware. In this paper,
we propose three new hardware architectures of fast search block matching motion estimation algorithm using Line Diamond Parallel
Search (LDPS) for H.264/AVC video coding system. These architectures use pipeline and parallel processing techniques and present
minimum latency, maximum throughput and full utilization of hardware resources. The VHDL code has been tested and can work
at high frequency in a Xilinx Virtex-5 FPGA circuit for the three proposed architectures. 相似文献
72.
The present paper is a contribution to the phenomenological modelling of fatigue non-linear cumulative diffuse damage in short glass fibre reinforced thermoplastic matrix composites. In such materials, fatigue damage kinetic exhibits three stages, namely: (i) material softening and damage initiation, (ii) coalescence and propagation of micro-cracks and (iii) macroscopic cracks propagation and material failure. The proposed model is built in the framework of the continuum damage mechanics and aims at predicting these three stages of the damage evolution. This model is based on the approach initially proposed by Ladevèze and Le Dantec [Ladevèze P, Le Dantec E. Damage modelling of the elementary ply for laminated composites. Comp Sci Technol 1992;43:257–67]. It extends the previous approach and takes into account the important stiffness reduction observed during the first damage stage. The above is modelled by the integration of a combined Norton-like power law and an exponential law expressing the damage rates as a function of the associated thermodynamic dual forces. The model has been formulated in terms of strain energy, so that makes easy its numerical implementation into the finite element code Abaqus/Standard through a user defined material subroutine UMAT. Numerical simulations are performed on a short glass fibre reinforced thermoplastic described by a given set of damage parameters. Damage evolutions predicted by the developed model reproduce well those observed for this kind of composites under cyclic loading. A parametric study is performed to understand the effects of the model parameters on the damage accumulation and their sensitivity on its kinetic. The sensitivity study would be useful since it contributes to optimise the ongoing experimental procedure aimed at identifying the damage model parameters. 相似文献
73.
Hessameddin Yaghoobi Abdolhossein Fereidoon Mohammad Khaksari Nouri Soraya Mareishi 《先进材料力学与结构力学》2015,22(10):864-875
In this study, the thermal buckling analysis of hybrid laminated plates made of two-layered functionally graded materials (FGMs) that are integrated with surface-bonded piezoelectric actuators referred to as (P/FGM)s are investigated. Material properties for both substrate FGM layers and piezoelectric layers are temperature-dependent. Uniform temperature rise as a thermal load and constant applied actuator voltage are considered for this analysis. By definition of four new analytic functions, the five coupled governing stability equations, which are derived based on the first-order shear deformation plate theory, are converted into fourth-order and second-order decoupled partial differential equations (PDEs). Considering a Levy-type solution, these two PDEs are reduced to two ordinary differential equations. One of these equations is solved using an accurate analytical solution, which is named as power series Frobenius method. The effects of parameters, such as the plate aspect ratio, ratio of piezoelectric layer thickness to thickness of FGM layer, gradient index, actuator voltage, and the temperature dependency on the critical buckling temperature difference, are illustrated and explained. The critical buckling temperatures of (P/FGM)s with six various boundary conditions are reported for the first time and can be served as benchmark results for researchers to validate their numerical and analytical methods in the future. 相似文献
74.
Nouri Mohammad Isfahani Amir Homayoon Meghdadi Shirneshan Alireza 《Clean Technologies and Environmental Policy》2021,23(8):2265-2284
Clean Technologies and Environmental Policy - This research investigates the effects of the addition of Fe2O3 and Al2O3 nanoparticles (30, 60 and 90 ppm) and Fe2O3–Al2O3 hybrid... 相似文献
75.
76.
Mohammad Mehdi Foroughi Shohreh Jahani Zahra Aramesh-Boroujeni Meisam Rostaminasab Dolatabad Kiana Shahbazkhani 《Ceramics International》2021,47(14):19727-19736
In this experiment, an original three-dimensional (3D) cubic of europium (Eu) 3+/cuprous oxide (Cu2O) with clover-like face-centered nanostructures (Eu3+/Cu2O CLFNs) was successfully synthesized to determine nevirapine (C15H14N4O), using electrochemical methods. The surface morphology of the Ns was correspondingly identified through different techniques, including energy dispersive X-ray spectroscopy (EDX), X-ray powder diffraction (XRD), and scanning electron microscopy (SEM). In this sense, the synergistic influence of the Eu3+/Cu2O CLFNs enhanced the electrocatalytic capability of the electrode via a modified glassy carbon (GC) and raised the active site. Employing various approaches, the modified electrode was then analyzed through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Moreover, kinetic parameters and electrochemical ones were estimated by means of voltammetric methods. For the determination of nevirapine applying the Eu3+/Cu2O CLFNs/GC electrode (GCE), differential pulse voltammetry (DPV) was further utilized. Under optimized conditions, the range of linear responses was between 0.01 and 750.0 μM with the limit of detection (LOD) of 3.6 nM, whereas the recommended sensor sensitivity was equal to 0.1244 μA/μM. The response time of approximately 3.5 min and the reproducibility (inter- and intra-electrode reproducibility of 2.26% and 1.51%, respectively) were subsequently achieved. It was concluded that sensors have been thus far exploited to determine nevirapine in real samples with favorable outcomes, indicating that electrocatalysis modifier can be assumed as one of appropriate catalysts. 相似文献
77.
Norouzi Shad Mozhdeh Maadani Mohsen Nesari Moghadam Meisam 《Wireless Personal Communications》2022,126(3):2249-2268
Wireless Personal Communications - With the emergence of Internet of Things (IoT) having large scale and generating huge amount of data, Intelligent Decision Support Systems (IDSSs) have attracted... 相似文献
78.
79.
AS Dajani KA Taubert W Wilson AF Bolger A Bayer P Ferrieri MH Gewitz ST Shulman S Nouri JW Newburger C Hutto TJ Pallasch TW Gage ME Levison G Peter G Zuccaro 《Canadian Metallurgical Quarterly》1997,128(8):1142-1151
OBJECTIVE: To update recommendations issued by the American Heart Association last published in 1990 for the prevention of bacterial endocarditis in individuals at risk for this disease. PARTICIPANTS: An ad hoc writing group appointed by the American Heart Association for their expertise in endocarditis and treatment with liaison members representing the American Dental Association, the infectious Diseases Society of America, the American Academy of Pediatrics and the American Society for Gastrointestinal Endoscopy. EVIDENCE: The recommendations in this article reflect analyses of relevant literature regarding procedure-related endocarditis, in vitro susceptibility data of pathogens causing endocarditis, results of prophylactic studies in animal models of endocarditis and retrospective analyses of human endocarditis cases in terms of antibiotic prophylaxis usage patterns and apparent prophylaxis failures. MEDLINE database searches from 1936 through 1996 were done using root words endocarditis, bacteremia and antibiotic prophylaxis. Recommendations in this document fall into evidence level III of the U.S. Preventive Services Task Force categories of evidence. CONSENSUS PROCESS: The recommendations were formulated by the writing group after specific therapeutic regimens were discussed. The consensus statement was subsequently reviewed by outside experts not affiliated with the writing group and by the Science Advisory and Coordinating Committee of the American Heart Association. These guidelines are meant to aid practitioners but are not intended as the standard of care or as a substitute for clinical judgment. CONCLUSIONS: Major changes in the updated recommendations include the following: (1) emphasis that most cases of endocarditis are not attributable to an invasive procedure; (2) cardiac conditions are stratified into high-, moderate- and negligible-risk categories based on potential outcome if endocarditis develops; (3) procedures that may cause bacteremia and for which prophylaxis is recommended are more clearly specified; (4) an algorithm was developed to more clearly define when prophylaxis is recommended for patients with mitral valve prolapse; (5) for oral or dental procedures the initial amoxicillin dose is reduced to 2 g, a follow-up antibiotic dose is no longer recommended, erythromycin is no longer recommended for penicillin-allergic individuals, but clindamycin and other alternatives are offered. 相似文献
80.
Wireless Personal Communications - The most usage of Mobile Ad-hoc Network in emergency and critical cases, needs a precise evaluation of its performance toward security challenges. Traditional... 相似文献