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81.
Healthcare organizations strive to make the best use of their organizational knowledge. The collective know-hows of the medical workers directly affect the quality of the delivered healthcare services. This study addresses the healthcare knowledge-sharing among a community of specialized physicians. An extensive study of the literature on knowledge-sharing in industries generally and healthcare organizations specifically were presented. Six focal elements were detected in previous attempts to address the knowledge-sharing status in healthcare organizations. Additionally, three previous models for healthcare knowledge management were analyzed. The studied literature along with the three studied models helped in constructing the framework and suggesting a suitable research methodology for primary data collection. Qualitative approach of in-depth interview technique was used for interviewing eight specialized physicians. The data collected from the interviewees were then analyzed and produced explanatory themes and codes. These themes are physicians’ acquisition of medical knowledge, staff participating in the knowledge sharing, knowledge-sharing culture, ICT-based knowledge sharing and top management involvement. The findings resulted in recognizing four considerations which ought to be taken into account for successful knowledge-sharing activities and learning initiatives in the healthcare organization. Conclusions and recommendations for future studies were presented based on the implications of this research study.  相似文献   
82.
Two soluble anthracene-based organic materials (BPA-An1 and BPA-An2) have been synthesized and characterized. The optical properties of these π-conjugated systems were investigated by UV–Visible absorption and photoluminescence (PL) spectroscopies. The optical gaps were estimated from the absorption onsets of the thin polymer films; their values were 3.01 and 2.76?eV for BPA-An1 and BPA-An2, respectively. The PL spectrum of BPA-An2 exhibits a blue emission both in dilute solution and thin film. BPA-An1 showed a blue photoluminescence in dilute solution; in solid film, π–π interactions influence its optical behavior and a green emission was observed. The HOMO and LUMO levels were estimated using cyclic voltammetry analysis. Single-layer devices of the (indium-tin oxide/anthracene-based material/aluminum) configuration have been elaborated and showed relatively low turn-on voltages of 6.2–5.5?V for BPA-An1 and BPA-An2, respectively.  相似文献   
83.
Epoxy thin film composites filled with particulate nanofillers; synthetic diamond and graphene nanoplatelets were prepared and characterized based on tensile, thermal, and electrical properties. The influences of these two types of fillers, especially in terms of their loading, sizes and shapes, were discussed. It was found that the epoxy thin film composites incorporating synthetic diamond displayed optimum properties where the addition of synthetic diamond from 0 to 2 vol.% results in higher elastic modulus, tensile strength, elongation at break, thermal conductivity and storage modulus if compared to those of graphene nanoplatelets composites. Both thin film composites showed improvement in the glass transition temperature with increasing filler loadings. Results on the electrical conductivity of both systems showed that higher conductivity is observed in graphene nanoplatelets composites if compared to synthetic diamond composites.  相似文献   
84.
Optically transparent, conductive, and mechanically flexible epoxy thin films are produced in the present study. Two types of multiwalled carbon nanotubes (MWCNTs) with different aspect ratios are dispersed in epoxy resin through an ultrasonication process. The MWCNT content is varied during the preparation of the thin films. The light transmittance and electrical conductivity of the thin films are characterized. Results show that composites containing MWCNTs with a lower aspect ratio exhibit enhanced electrical conductivity compared to those with a higher aspect ratio. A sheet resistance as low as 100 Ω/sq with nearly 60% optical transparency in 550 nm is achieved with the addition of MWCNTs in epoxy. In summary, transparent, conductive, and flexible MWCNT/epoxy thin films are successfully produced, and the properties of such films are governed by the aspect ratio and content of MWCNTs.  相似文献   
85.
In this paper, we propose a method for evaluation of the bit error rate (BER) for packet combining based on constellation rearrangement (CoRe). Such mapping diversity scheme, adopted in the high speed downlink packet access (HSDPA), uses Gray‐mapped constellations and is based on suboptimal accumulation of the reliability metrics generated in each of the transmissions. We present an exact model for the logarithmic likelihood ratios (LLR) obtained by means of the so‐called max‐log approximation, and we show that their conditional probability density functions (pdf) are piecewise Gaussian. We then present the derivation of the uncoded BER and illustrate it with simulation results that confirm our formulation. Finally, we propose simplifications which significantly reduce the complexity of the evaluation method and provide results with a very good accuracy; an extension to transmissions over faded channel is also presented. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
86.
Engineered nanoparticles (ENPs), such as metallic or metallic oxide nanoparticles (NPs), have gained much attention in recent years. Increasing use of ENPs in various areas may lead to the release of ENPs into the environment and cause the contamination of agricultural and food products by ENPs. In this study, we selected two important ENPs (zinc oxide [ZnO] and silver [Ag] NPs) as potential food contaminants and investigated their toxicity via an in vitro model using Caco‐2 cells. The physical properties of ENPs and their effects on Caco‐2 cells were characterized by electron microscopy and energy dispersive X‐ray spectroscopic (EDS) techniques. Results demonstrate that a significant inhibition of cell viability was observed after a 24‐h of exposure of Caco‐2 cells to 3‐, 6‐, and 12‐mM ZnO NPs or 0.5‐, 1.5‐, and 3‐mM Ag NPs. The noticeable changes of cells include the alteration in cell shape, abnormal nuclear structure, membrane blebbing, and cytoplasmic deterioration. The toxicity of ZnO NPs, but not that of Ag NPs after exposure to simulated gastric fluid, significantly decreased. Scanning transmission electron microscopy shows that ZnO and Ag NPs penetrated the membrane of Caco‐2 cells. EDS results also confirm the presence of NPs in the cytoplasm of the cells. This study demonstrates that ZnO and Ag NPs have cytotoxic effects and can inhibit the growth of Caco‐2 cells.  相似文献   
87.
This work aims to study the effects of date stone flour (DSF) on morphology, thermal, and mechanical properties of polypropylene (PP) composites in the absence and presence of ethylene‐butyl acrylate‐glycidyl methacrylate (EBAGMA) used as the compatibilizer. DSF was added to the PP matrix at loading rates of 10, 20, 30, and 40 wt %, while the amount of compatibilizer was fixed to the half of the filler content. The study showed through scanning electron microscopy analysis that EBAGMA compatibilizer improved the dispersion and the wettability of DSF in the PP matrix. Thermogravimetric analysis (TGA) indicated a slight decrease in the decomposition temperature at onset (Tonset) for all composite materials compared to PP matrix, whereas the thermal degradation rate was slower. Differential scanning calorimetry (DSC) data revealed that the melting temperature of PP in the composite materials remained almost unchanged. The nucleating effect of DSF was however reduced by the compatibilizer. Furthermore, the incorporation of DSF resulted in the increase of stiffness of the PP composites accompanied by a significant decrease in both the stress and strain at break. The addition of EBAGMA to PP/DSF composites improved significantly the ductility due to the elastomeric effect of EBAGMA. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
88.
Epoxy polymers are commonly utilized in structural applications due to their high bearing capacity and excellent chemical resistance. However, their inherent brittleness poses a significant challenge for their use in high shock and fracture strength products. To address this shortcoming, fillers can be incorporated into the polymer during preparation. In this study, we aimed to investigate the effect of incorporating cellulose-based fillers, namely cellulose nanocrystals (CNCs) and microcrystalline cellulose (MCC), on the mechanical properties of epoxy polymer composites. The study evaluated the impact of various factors, including filler concentration, particle size, and moisture content, on the mechanical properties of the composites. The results demonstrated that the incorporation of CNC or MCC powders at concentrations below 5% could enhance the mechanical properties of the resulting epoxy composites without adversely affecting their surface and thermal properties. The maximum tensile strength and fracture toughness of the filler-based epoxy composites were achieved at 2 and 4 wt% for CNCs and MCC, respectively. CNCs with a smaller particle size distribution were found to be much more effective than MCC in improving the mechanical properties of the epoxy composites. Furthermore, utilizing dried fillers resulted in a higher improvement in tensile strength, which was achieved at lower filler concentrations.  相似文献   
89.
Test cost is one of the main factors determining the profit margin of a device in production. Current test strategies require hundreds of measurements to determine the specifications of a parameter. In this paper, we present an automatic test-vector generation technique that is based on transfer function manipulation and requires only one circuit simulation. The proposed method consists of generating the first set of vectors by applying a derivation technique to the golden transfer function of the circuit under test (CUT). An interpolation technique allows a new transfer function to be constructed based on the first set of test vectors. The difference between the reconstructed transfer function and the golden transfer function is used to select the second set of test vectors. These new test vectors are selected to achieve the best possible fit. Our technique reduces the test vector size to values that at present can be achieved only by using powerful and time-consuming fault simulation tools. As an example, we apply the method to state variable and Chebyshev filters. We also compute the fault coverage in order to demonstrate the effectiveness of this new technique.  相似文献   
90.
A feasibility study on hydrogen production from wind power on the site of Ghardaia is carried out. This study is based on the estimation of the hydrogen rate produced by a 5 kW electrolyser fed by the electricity provided by a 10 kW wind turbine.Wind speed data were used to study the monthly variation of the wind power delivered and its variation according to the height of the wind turbine tower.The obtained results show that it is possible to improve the system output by increasing the height of the wind turbine tower. Indeed, it has been obtained 3200 Nm3 of hydrogen production for a 30 m wind turbine height and 4200 Nm3 at 60 m.In addition, it has been noticed that hydrogen production varies strongly with the months of the year. Thus, the production has reached a maximum of 395 Nm3 in May and a minimum of 187 Nm3 during November and October.  相似文献   
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