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11.
Applied Intelligence - Nowadays, healthcare waste management has become one of the significant environmental, health, and social problems. Due to population and urbanization growth and an increase...  相似文献   
12.
In this paper, we present the performance of multi-antenna selective combining decode-and-forward (SC-DF) relay networks over independent but non-identical Nakagami-m fading channels with imperfect channel estimation. The outage probability, moment generating function (MGF) and symbol error probability (SEP) will be derived in closed-form using the SNR statistical characteristics. To make the analysis trackable, we have derived the MGF and SEP for integer values of fading severity, m. Also, to make the relations more simple, we develop high signal to noise ratio (SNR) analysis for the performance metrics of our system. Subsequently, we propose optimal and adaptive power allocation algorithms along with the equal power allocation method. Finally, for comparison with analytical formulas, we perform some Monte-Carlo simulations.  相似文献   
13.
This study proposes a versatile criterion for estimating quality of images in electrical impedance tomography. The point spread function (PSF) is calculated throughout the domain based on the scattering of energy as responses to a small anomaly spirally moved from the centre to the boundary. The proposed PSF is a measure of weighted spatial variance (WSV) of the conductivity over the whole domain. For each element, the weighting factor is a normalized multiplication of the area of that element by its square intensity. The WSV collectively incorporates all image attributes, i.e., spatial resolution, artifact, amplitude response, positioning error and shape deformation. The location of artifacts, which significantly influences reconstructed images in reality, is taken into account as well. The results illustrate that the proposed measure is more tolerant than existing criteria in evaluating performance of EIT systems in both theory and practice.  相似文献   
14.
The phytochemicals content and radical scavenging activity of pistachio (Pistacia vera L.) hull extract obtained by different solvents (water, ethanol, and butanol) were measured and compared. Water was selected as superior solvent. Ultrasound-assisted aqueous extraction of the hull by power ultrasound (35 kHz) was more efficient in ascending the phytochemicals content than the sonochemical ultrasonication (130 kHz). High-performance liquid chromatography-mass spectrometry showed increased amounts of vanillic acid, p-coumaric acid, naringenin, and catechin in ultrasound-assisted extracts. Post-extraction sonication declined significantly the phenolics amount and antioxidant property of the aqueous extract. Microwave-assisted extraction increased the phenolics and flavonoids content at extract in a power-dependent trend.  相似文献   
15.
This paper investigates the potential of pulsed power to sterilize hard and soft tissues and its impact on their physico-mechanical properties. It hypothesizes that pulsed plasma can sterilize both vascular and avascular tissues and the transitive layers in between without deleterious effects on their functional characteristics. Cartilage/bone laminate was chosen as a model to demonstrate the concept, treated at low temperature, at atmospheric pressure, in short durations and in buffered environment using a purposed-built pulsed power unit. Input voltage and time of exposure were assigned as controlling parameters in a full factorial design of experiment to determine physical and mechanical alteration pre- and post-treatment. The results demonstrated that, discharges of 11 kV sterilized samples in 45 s, reducing intrinsic elastic modules from 1.4 ± 0.9 to 0.9 ± 0.6 MPa. There was a decrease of 14.1 % in stiffness and 27.8 % in elastic-strain energy for the top quartile. Mechanical impairment was directly proportional to input voltage (P value < 0.05). Bacterial inactivation was proportional to treatment time for input voltages above 32 V (P < 0.001; R Sq  = 0.98). Thermal analysis revealed that helix-coil transition decelerated with exposure time and collagen fibrils were destabilized as denaturation enthalpy reduced by 200 μV. We concluded by presenting a safe operating threshold for pulsed power plasma as a feasible protocol for effective sterilization of connective tissues with varying level of loss in mechanical robustness which we argue to be acceptable in certain medical and tissue engineering application.  相似文献   
16.
Intel's XeonPhi is a highly parallel x86 architecture chip made by Intel. It has a number of novel features which make it a particularly challenging target for the compiler writer. This paper describes the techniques used to port the Glasgow Vector Pascal Compiler to this architecture and assess its performance by comparisons of the XeonPhi with 3 other machines running the same algorithms. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
17.
This study aims to investigate how the predeposition machining processes such as magnetic grinding, turning machining, and wire electrical discharge machining can influence the surface properties including electrochemical and tribological behavior of TiCrN nanostructured coating applied on Mo40 steel substrate. A physical vapor deposition technique using cathodic arc evaporation was used to apply the coating. The crystallographic phases and the microstructure of the coating were studied by X-ray diffraction and scanning electron microscope, respectively. Rockwell-C, electrochemical impedance spectroscopy and potentiodynamic polarization, and pin-on-disk wear tests were employed to evaluate the adhesion strength, corrosion behavior, and tribological property of specimens, respectively. The electrochemical results after 24 h of exposure to 3.5 wt% NaCl solution showed that TiCrN coating pretreated with a turning process with polarization resistance of about 3525.32 Ω.cm2 had the best corrosion resistance among all specimens. This was because of the improvement of the smoothness, surface quality, and adhesion after the turning process. On the other, the friction coefficient of the grounded sample is less than that of other ones. This is probably due to its higher adhesion strength and higher surface smoothness.  相似文献   
18.
Graphene oxide (GO) film was evaporated onto graphite and used as an electrode to produce electrochemically reduced graphene oxide (ERGO) films by electrochemical reduction in 6 M KOH solution through voltammetric cycling. Fourier transformed infrared and Raman spectroscopy confirmed the presence of ERGO. Electrochemical impedance spectroscopy characterization of ERGO and GO films in ferrocyanide/ferricyanide redox couple with 0.1 M KCl supporting electrolyte gave results that are in accordance with previous reports. Based on the EIS results, ERGO shows higher capacitance and lower charge transfer resistance compared to GO.  相似文献   
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20.
Ashkan Vaziri 《Thin》2009,47(6-7):692-700
Emergence of new technological applications, in addition to the constantly growing interest in biological materials has accentuated the importance of studying the mechanics of highly deformed shells. The key challenge is the intricate interplay of physics and geometry, which leads to a mechanical response much different from the response of solid objects. The quest to understand the underlying phenomena has spawned theoretical and experimental studies, which have helped in understanding the underlying mechanisms of deformation and response of shells. Here, we use numerical simulations to study the response of shells when they are deformed deeply into the nonlinear regime. We use computational models to study the mechanics of highly deformed elastic shells in several classical problems: indentation of elastic spherical caps by a flat rigid plate and a rigid sharp indenter and pure bending of circular and oval cylinders. These assays are used to highlight some of the key aspects of the mechanics of highly deformed elastic shells, while an overview of the current state-of-the-art and suggestions for future research on this subject are also provided.  相似文献   
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