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1.
Journal of Porous Materials - Solar vapor generation is considered a green and practical approach to take advantage of solar energy as a renewable source and provide pure water. However, developing...  相似文献   
2.
Many occupations require workers to stand for long periods of time without proper interventions, which causes discomfort in the back and lower limbs. Therefore, this study aims to assess the effectiveness in alleviating body muscle discomfort during prolonged standing through the use of a calf massager. This study was conducted among male workers at a manufacturer with production line workers and the list was obtained from the HR Department and simple random sampling was done by number categorization. A total of 100 respondents (50 respondents for both the control and the experimental groups) participated in this study. The experiment took place in a room with a similar setup for the production line. Each respondent was requested to perform the simulated task for 2 hr. For the experimental group, the calf massager was turned on every 15 min. At every 15‐min interval after turning on the calf massager, respondents from both groups were required to evaluate their discomfort level on a Borg's scale CR‐10 questionnaire. The results showed that the level of body discomfort among respondents in the experimental group reduced (20–30%) compared with that of the control group. Multivariate analysis results revealed that the discomfort rating for the lower back, knees, thighs, calves, and feet was significantly lower (p < .05) among the experimental group compared with the control group. For lower body parts, the lower back region was statistically significant (p < .05) at the 90th, 105th, and 120th min; the thigh region was statistically significant (p < .05) at the 120th min; the knee region was statistically significant (p < .05) at the 105th and 120th min; the calf region was statistically significant (p < .05) at all minute intervals except the 15th and 45th min, while the feet region, was statistically significant at the 105th and 120th min. Therefore, this study indicates that calf massage treatment is capable of reducing body muscle discomfort during prolonged standing and highlights the significance of calf massage.  相似文献   
3.
In crack detection and sizing by the alternating current field measurement technique, U-shaped wires or coils excited by a high-frequency AC current source can be used to induce the surface field in the workpiece. The authors present a modeling technique for the interaction of a fatigue crack in a ferromagnetic metal with the surface field resulting from an inducer with two U-shaped wires. This work is an extension of a previous modeling technique to have developed for infinitely long (one-dimensional) cracks. In the present technique, the boundary of the fatigue crack is approximated by a circular arc, leading to a formulation for an efficient computation of the field-flaw interaction. Various numerical and experimental results supporting the modeling and illustrating the behavior of the magnetic field and electric potential at the metal surface around circular-arc cracks are presented  相似文献   
4.
We simulate the charge carrier traffic between the energy bands and the interface states in structures like Al/SiO2/6H–SiC, Al/diamond/Si and Al/SIPOS/Si to explain their high frequency capacitance–voltage behavior. The structures have in common that traditional electrical measurement techniques performed at room temperature are prone to thermal non-equilibrium effects. This can result in large errors in the interface data extracted from such studies when thermal equilibrium conditions are assumed. In this work, high frequency capacitance–voltage data are compared to numerical simulations which include such thermal non-equilibrium conditions to enable more accurate estimates of interface state parameters in above-mentioned structures.  相似文献   
5.
Thin CdS films have been grown by chemical bath (CdCl2, thiourea, ammonia) deposition (CBD) on SnO2 (TO)-coated glass substrate for use as window materials in CdS/CdTe solar cells. High-resolution transmission electron microscopy revealed grains with an average size of 10 nm. The structure was predominantly hexagonal with a high density of stacking faults. The film crystallinity improved with annealing in air. Annealing in a CdCl2 flux increased the grain size considerably and reduced the density of stacking faults. The optical transmission of the as-deposited films indicated a band gap energy of 2.41 eV. Annealing in air reduced the band gap by 0.1 eV. Annealing in CdCl2 led to a sharper optical absorption edge that remained at 2.41 eV. Similar band gap values were obtained by photocurrent spectroscopy and electroabsorption spectroscopy (EEA) using an electrolyte contact. EEA spectra were broad for the as-deposited and air-annealed samples, but narrower for the CdCl2-annealed films, reflecting the reduction in stacking fault density. Donor densities of ca. 1017 cm –3 were derived from the film/electrolyte junction capacitance.  相似文献   
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7.
Healthcare delivery is evolving from disease-centered to patient-centered care delivery where patients are active participants in their healthcare delivery. This calls for more communication and collaboration among all healthcare actors. There is also an increasing demand for personalized healthcare systems that provide effective information management, facilitate communication and collaboration, and support applications to meet user requirements. To address these challenges, we need to advance the integration and interoperability of healthcare applications in a controlled manner. Drawing upon a conceptual model from a collaborative care case study, we identified a set of interoperability requirements and developed a Mashup based interoperability framework. Our framework allows patients and other healthcare actors to engage in collaborative processes through online applications facilitated by mashups. We then use proof-of-concept implementations to demonstrate how our framework is able to facilitate different types of interoperability. We believe that collaborative technologies such as mashups can implement process interoperability requirements to support collaborative care delivery, particularly for asynchronous care delivery.  相似文献   
8.
Consideration is given to the buoyancy effects on the fully developed gaseous slip flow in a vertical rectangular microduct. Two different cases of the thermal boundary conditions are considered, namely uniform temperature at two facing duct walls with different temperatures and adiabatic other walls (case A) and uniform heat flux at two walls and uniform temperature at other walls (case B). The rarefaction effects are treated using the first-order slip boundary conditions. By means of finite Fourier transform method, analytical solutions are obtained for the velocity and temperature distributions as well as the Poiseuille number. Furthermore, the threshold value of the mixed convection parameter to start the flow reversal is evaluated. The results show that the Poiseuille number of case A is an increasing function of the mixed convection parameter and a decreasing function of the channel aspect ratio, whereas its functionality on the Knudsen number is not monotonic. For case B, the Poiseuille number is decreased by increasing each of the mixed convection parameter, the Knudsen number, and the channel aspect ratio.  相似文献   
9.
Neural Processing Letters - Deep learning is an important subcategory of machine learning approaches in which there is a hope of replacing man-made features with fully automatic extracted features....  相似文献   
10.
The effects of gum tragacanth obtained from two species of Astragalus Gossypinus (GT-G) and A. Parrowianus (GT-P) at two levels of 10% and 30% combined with cellulose nanofibers (CNF; 5%) on the physico-mechanical and structural properties of polyvinyl alcohol (PVA) nanocomposite film were investigated in this study. The water solubility and water vapor permeability of the films decreased with increasing the content of both gums, especially in the film containing 30% GT-P. The highest values of the tensile strength (39.3 MPa) and elongation at break (445%) belonged to the treatment containing 10% GT-P (90/10P/0). The FTIR and DSC analyses confirmed good interactions between GT and PVA in the 90/10P/0 treatment. SEM images indicated the dense structure of this film as the optimum treatment. Although the presence of CNF in the films containing GT-G improved some properties, especially the Young modulus, it impaired all the functional properties of nanocomposite GT-P film.  相似文献   
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