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排序方式: 共有1066条查询结果,搜索用时 46 毫秒
1.
Singh Nalin Rathore Santosh Singh Kumar Sandeep 《Multimedia Tools and Applications》2022,81(27):38887-38919
Multimedia Tools and Applications - The video surveillance activity generates a vast amount of data, which can be processed to detect miscreants. The task of identifying and recognizing an object... 相似文献
2.
Wireless Personal Communications - In recent years, the emergence of Internet of things and cyber-physical system provide a proactive and efficacious solution to enable remote monitoring, machine... 相似文献
3.
Manoj Karakoti Ritu Jangra Sandeep Pandey Pawan Singh Dhapola Sunil Dhali Suman Mahendia Pramod K Singh Nanda Gopal Sahoo 《International Journal of Applied Ceramic Technology》2020,17(4):1899-1908
This study deals with the utility of mini spray dryer process to improve the dispersibility, of graphene oxide(GO) and its application for high-performance supercapacitor. Initially, the neutral solution of GO was obtained using the modified Hummer's method. After this, the prepared GO solution was processed by mini spray dryer to obtain a more purified, lighter, and dispersed form of GO which is named as spray dryer processed GO (SPGO). The SPGO thus obtained showed excellent dispersibility behavior with various solvents, which is not found in case of conventional oven drying. Furthermore, utility of SPGO and its reduced form (r-SPGO) for supercapacitor applications have been investigated. Results obtained from the cyclic voltammetry(CV) analysis, impedance, and charge-discharge behavior of supercapacitor fabricated using r-SPGO shows enhanced features. Therefore, the simple spray dried GO and its reduced form, that is, r-SPGO can be utilized as a potential candidate for the supercapacitor application. Herein, as synthesized SPGO exhibited the specific capacitance of 12.07 and 37.6 F/g with PVA-H3PO4 and 1 mol/L H3PO4, respectively, at a scan rate of 5 mV/s. On the other hand, reduced form of SPGO, that is, r-SPGO showed the specific capacitance of 27.16 and 230 F/g with PVA-H3PO4 and 1 mol/L H3PO4, respectively. 相似文献
4.
Poly(ethylene aspartate) [PEA] was synthesized by the melt condensation of D,L-aspartic acid and ethylene glycol. PEA containing pendent amino and carbonyl groups in its repeating chain was used as the polymeric ligand for complexation with transition metal ions, viz. Co(II), Ni(II), Cu(II), Mn(II), Zn(II), Cd(II), Ca(II), Mg(II), Pb(II) and Hg(II). Complexation was found to be most effective in DMSO. The resulting polyester-metal complexes were solid coloured materials which have been characterized by IR spectroscopy, elemental analysis and magnetic susceptibility measurements. The thermal stability of the polyester-metal complexes was investigated by thermogravimetric analysis (TGA). On the basis of the physico-chemical studies, an oxygen and nitrogen coordinated structure for the polyester-metal complexes is proposed. 相似文献
5.
Arata L.K. Dhawan A.P. Broderick J.P. Gaskil-Shipley M.F. Levy A.V. Volkow N.D. 《IEEE transactions on bio-medical engineering》1995,42(11):1069-1078
Model-based segmentation and analysis of brain images depends on anatomical knowledge which may be derived from conventional atlases. Classical anatomical atlases are based on the rigid spatial distribution provided by a single cadaver. Their use to segment internal anatomical brain structures in a high-resolution MR brain image does not provide any knowledge about the subject variability, and therefore they are not very efficient in analysis. The authors present a method to develop three-dimensional computerized composite models of brain structures to build a computerized anatomical atlas. The composite models are developed using the real MR brain images of human subjects which are registered through the principal axes transformation. The composite models provide probabilistic spatial distributions, which represent the variability of brain structures and can be easily updated for additional subjects. The authors demonstrate the use of such a composite model of ventricular structure to help segmentation of the ventricles and cerebrospinal fluid of MR brain images. Here, a composite model of ventricles using a set of 22 human subjects is developed and used in a model-based segmentation of ventricles, sulci, and white matter lesions. To illustrate the clinical usefulness, automatic volumetric measurements on ventricular size and cortical atrophy for an additional eight alcoholics and 10 normal subjects were made. The volumetric quantitative results indicated regional brain atrophy in chronic alcoholics 相似文献
6.
Due to technology scaling and increasing clock frequency, problems due to noise effects lead to an increase in design/debugging efforts and a decrease in circuit performance. This paper addresses the problem of efficiently and accurately generating two-vector tests for crosstalk induced effects, such as pulses, signal speedup and slowdown, in digital combinational circuits. These noise effects can propagate through a circuit and create a logic error in a latch or at a primary output. We have developed a mixed-signal test generator, called XGEN, that incorporates classical static values as well as dynamic signals such as transitions and pulses, and timing information such as signal arrival times, rise/fall times, and gate delay. In this paper we first discuss the general framework of the test generation algorithm followed by computational results. Comparison of results with SPICE simulations confirms the accuracy of this approach. 相似文献
7.
An electrically conductive plastic material was obtained by the polymerization of pyrrole on insulating polymeric materials
and nylon cloth impregnated with the oxidant by vapour phase technique, resulting in a uniform, smooth and adherent coating
of conducting polymer having a surface resistance ranging from 200 Ω/□ to 20 kΩ/□, which makes it suitable for applications
as an antistatic material. 相似文献
8.
A Antonini JR Moeller T Nakamura P Spetsieris V Dhawan D Eidelberg 《Canadian Metallurgical Quarterly》1998,51(3):803-810
OBJECTIVE: To identify regional metabolic brain networks related specifically to the presence of tremor in PD. BACKGROUND: The pathophysiology of parkinsonian tremor is unknown. Because tremor in PD occurs mainly in repose, we used resting state PET with 18F-fluorodeoxyglucose (FDG) to identify specific metabolic brain networks associated with this clinical manifestation. METHODS: We studied two discrete groups of eight PD patients with and without tremor using FDG/PET. Both patient groups were matched for gender, age, and Unified Parkinson Disease Rating Scale ratings for akinesia and rigidity. Ten normal volunteer subjects served as controls. RESULTS: Network analysis with the Scaled Subprofile Model was performed in two steps. 1) We computed the expression of the PD-related pattern (PDRP) identified by us previously in each of the PD patients and control subjects. Although PDRP subject scores were abnormally elevated in the combined PD cohort (p < 0.005), these values did not differ in the PD patient groups with and without tremor (p = 0.36). 2) We used SSM to analyze the data from the combined PD cohort comprising both patient groups. We found that PD patients with tremor were characterized by increased expression of a metabolic network comprising the thalamus, pons, and premotor cortical regions. Subject scores for this pattern were elevated in the tremor group compared with the atremulous patient group and the normal control group (p < 0.005). CONCLUSIONS: The findings suggest that PD patients with tremor are characterized by distinct increases in the functional activity of thalamo-motor cortical projections. Modulation of this functional anatomic pathway is likely to be the mechanism for successful interventions for the relief of parkinsonian tremor. 相似文献
9.
Gallium telluride (Ga2Te3) was synthesized at different temperatures (850 to 460° C) using different cooling rates. Materials synthesized at higher temperatures (including quenched materials from the melt) always yielded zinc-blende lattice with well resolved
1
2 doublet X-ray powder diffraction lines. In the material synthesized at lower temperature ( 460°C), we obtained additional (superlattice) lines as reported by Newman and Cundall [4]. It was possible to index these reflections not only on an orthorhombic unit cell (a=0.417, b=2.360, c=1.252 nm) but also on cubic (a=1.7678 nm) and hexagonal (a=0.832, c=3.065 nm) unit cells. To us, the hexagonal cell appears to be more realistic. If sufficient time is given to reach equilibrium, the whole of the zinc-blende form of Ga2Te3 is transformed to the hexagonal form. It has been further observed that conversion of the hexagonal into the cubic form and vice versa can be brought about by heating the material at temperatures greater or less than 460° C, respectively. Lastly, the zinc-blende phase of Ga2Te3 is metastable and slowly transforms to hexagonal form at room temperature. 相似文献
10.
Glass fiber-reinforced epoxy composites were prepared from the matrix resins tetraglycidyl diaminodiphenylmethane 1 Systematic name: N,N,N′,N′-Tetrakis(2,3-epoxypropyl)-4,4′-diaminodiphenylmethane. (TGDDM) and tetraglycidyl bis(o-toluidino)-methane 2 Systematic name: N,N,N′,N′-Tetrakis(2,3-epoxypropyl)-4,4′-bis(o-toluidino)methane. (TGMBT) using various amines like 4,4′-diaminodiphenylmethane (DDM), 4,4′-diaminodiphenylsulfone (DDS) and diethylene triamine (DETA) as curing agents. The fabricated laminates were evaluated for their mechanical and dielectrical properties and chemical resistance. The composites prepared using an epoxy fortifier (20 phr) showed significant improvement in the mechanical properties. 相似文献