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51.
A neuro-fuzzy model for diagnosis of psychosomatic disorders is proposed in this paper. The symptoms and signs are collected from the patients through oral interview. For the linguistic nature of patient's inputs, an artificial domain is created and fuzzy membership values are defined. The fuzzy values are fed as inputs to feedforward multilayer neural network. The network is trained using Backpropagation training algorithm. The trained model is tested with new patient's symptoms and signs. Further, the performance of the diagnosing capability is compared with medical expert. The performance of the model is also compared with probability model based on Bayesian Belief Network and statistical model using Linear Discriminant analysis 相似文献
52.
Great efforts have been made in analyzing the strength of notched laminates under in-plane loadings. However, no work has been reported on notched laminates under bending, because of the complexity of theoretical stress analysis. In this study, a simplified approach has been used to analyze the notched strength of laminated composites with an elliptical hole under bending. This approach combines notched sample experiments and finite element results. Based upon the consideration that not only the stress distribution at one ply, but also the stress variation across the laminate thickness, should be taken into account, two failure models are presented: a modified point stress model and a modified average stress model. Two characteristic parameters are presented to evaluate the notched strength of the laminated plates. 相似文献
53.
Future high speed mobile applications require diverse Quality of Service (QoS). To provide flexible data rate services while
satisfying the low delay requirements, adaptive MIMO OFDM is a promising technique over time varying channels. In this paper
a variable power adaptive MIMO OFDM system under imperfect CSI using cross layer design for mobile ad hoc networks is proposed.
Data throughput is maximized while maintaining the delay QoS requirements in the presence of channel estimation errors. Numerical
results show that the variable power adaptive MIMO OFDM system provides better spectral efficiency than its constant power
counterpart. 相似文献
54.
I. Aruna B.R. Mehta L.K. Malhotra S.M. Shivaprasad 《Advanced functional materials》2005,15(1):131-137
Gadolinium nanoparticles, deposited via an inert gas evaporation method, show improved stability towards oxidation and it is therefore possible to carry out an ex‐situ investigation on “bare” Gd nanoparticles, i.e., in the absence of a protective Pd layer, for the first time. A size‐induced structural transformation from hexagonal close packing to the higher‐symmetry face‐centered cubic structure is observed. The important observation of hydrogen–Gd‐nanoparticle interaction at room temperature and atmospheric pressure, without a Pd catalytic layer, makes Gd nanoparticles a potential candidate for hydrogen‐sensing, switching, and storage applications. 相似文献
55.
Seneke Chamith Chandrarathna Sontyana Adonijah Graham Muhammad Ali Arambewaththe Lekamalage Aruna Kumara Ranaweera Migara Lakshitha Karunarathne Jae Su Yu Jong-Wook Lee 《Advanced functional materials》2023,33(17):2213900
A self-powered system for the Internet of Things (IoT) is demonstrated for efficient energy harvesting of naturally available mechanical energy. In this system, new contact-separation mode triboelectric nanogenerators (TENGs), based on fluorinated ethylene propylene, are investigated using the segmented multi-TENG configuration to reduce the effect of parasitic capacitance. The TENG extraction is optimized using a unit step excitation involved with the Dawson function to achieve a high voltage (400 V) and a high current (26.6 µA). To fully extract the power of the TENGs, the power management integrated circuit (PMIC) specially designed for adaptively controlled, high-voltage (HV) maximum power point tracking (MPPT) is proposed. The PMIC implemented in a bipolar CMOS-DMOS 180 nm process can handle a wide input range (5–70 V) by consuming 420 nW. The MPPT control allows a wide range of impedance matching from 10 to 300 MΩ, achieving a tracking efficiency of up to 98.2%. The end-to-end efficiency of 88% demonstrates state-of-the-art performance. To supply a higher instantaneous power than that available from the TENGs, a duty-cycling technique is successfully demonstrated. The proposed energy harvesting system provides a promising approach to realizing sustainable and autonomous energy sources for various IoT applications. 相似文献
56.
The frequency of micronuclei was evaluated in the bone marrow of mice of either sex administered with 0, 0.625, 1.25, 2.5, 5, 10, 20, 40 and 80 mg/kg b.wt of lead nitrate at 12, 24 and 36 h post-treatment. The frequency of micronucleated polychromatic erythrocytes (MPCE) and micronucleated normochromatic erythrocytes (MNCE) increased significantly at 12, 24 and 36 h after treatment with lead nitrate compared to non-drug treated controls. The frequency of micronuclei did not show a dose related increase and the elevation in the frequency of micronuclei was fluctuating type. One important observation which emerged from this study was that the male mice were more sensitive to the induction of micronuclei compared to female mice. This was evidenced by higher frequencies of MPCE in males than females at all the doses for all the post-treatment time periods. The lead nitrate treatment resulted in a spurt in the erythropoiesis as is evidenced by a significant increase in the ratios of polychromatic to normochromatic erythrocytes (P/N ratio) compared to non-drug treated controls at 12, 24 and 36 h post-treatment. The P/N ratio was significantly higher in females than males at 12 and 24 h post-treatment. 相似文献
57.
K. V. Ojha Aruna Tomar Devendra Singh G. C. Kaushal 《Transactions of the Indian Institute of Metals》2008,61(2-3):139-143
Manufacturing process through spray forming leads to give near-net-shape and fine grain microstructure. In this process Si particles, which are not distributed uniformly in conventional casting process, are distributed uniformly throughout the casting. In the present study disc shape spray form castings were made of Al-6.91Si and Al-10.1Si alloys, and then their shape, wear and mechanical properties were studied. The shape of the deposit was observed to be the most uniform at 30o inclination angle of the substrate. The hardness and tensile strength value of spray formed alloys shows the increment in the mechanical property in contrast to as cast alloys. The wearing properties of Al-10.1Si alloy were found to be better than that of the Al-6.91Si alloy. 相似文献
58.
Poly(urethane semicarbazide) anionomers containing azobenzene chromophores in the main chain were prepared by chain extending the isocyanate terminated prepolymers with chromophoric dihydrazide. Variations were done with respect to the hard segment content and the nature of the diisocyanate and the effect of the variations on the thermal, mechanical properties and wettability were studied. The polymers in solution showed reversible photoisomerization behaviour evinced by UV/vis spectroscopy in which irradiation of polymer solutions with UV light was observed as a decrease in intensity of absorbance corresponding to trans-form and increase in the absorbance of cis-form. The back relaxation took place in the presence of visible light. Photoswitching or the wettability of the films induced by the reversible cis–trans isomerization of the azobenzene chromophores was experimentally shown from water contact angle measurements. Irradiation of the films with 365 nm light effected a decrease in the water contact angle. X-ray diffraction results indicated dense arrangement of crystallized hard segments in compositions containing higher hard segment content. Thermal stability up to 300 °C was exhibited by the polymers as shown by thermogravimetric analysis and the phase separated morphology was confirmed by dynamic mechanical analysis. Tensile strength measurements showed that the films with increasing hard segment content exhibited increasing tensile strength and modulus but decreasing values of elongation. 相似文献
59.
Aruna Velamakanni K. J. Ganesh Yanwu Zhu Paulo J. Ferreira Rodney S. Ruoff 《Advanced functional materials》2009,19(24):3926-3933
Catalyst‐free growth of boron carbide nanowires is achieved by pyrolysis of diborane and methane at 650–750 °C and around 500 mTorr in a quartz tube furnace. Electron‐diffraction analysis using a novel diffraction‐scanning transmission electron microscopy (D‐STEM) technique indicates that the crystalline nanowires are single‐crystal orthorhombic boron carbide. TEM images show that the nanowires are covered by a 1–3 nm thick amorphous layer of carbon. Elemental analysis by electron energy loss spectroscopy (EELS) shows only boron and carbon while energy‐dispersive X‐ray spectroscopy (EDX) and X‐ray photoelectron spectroscopy (XPS) show the presence of oxygen as well as boron and carbon. 相似文献
60.
Plasma sprayable grade ceria powder was prepared by the solution combustion method. This is the first report on the application of solution combustion for the synthesis of plasma sprayable grade oxide powders. The fuels and fuel ratios used in the solution combustion were modified to achieve adequate flowability. It was found that when a mixture of fuels like glycine and ammonium acetate was used, the combustion process yielded larger agglomerates. Phase purity of the powders was confirmed by powder XRD. The morphology of the particles was determined by scanning electron microscopy. 相似文献