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281.
Snigdha Panigrahi Sarama Bhattacharjee Laxmidhar Besra Bimal P. Singh S.P. Sinha 《Journal of the European Ceramic Society》2010,30(5):1097-1103
Electrophoretic deposition of doped ceria has been carried out in non-aqueous solvent to prepare coatings on different substrates and free standing films. It has been found that uneven deposition occurred in ethanol, while in butanol deposition yield is low having very little variation with deposition time. On the other hand, good deposit obtained in acetyl acetone medium, but had a porous structure. The best result however was obtained in mixed solvent. Effect of adding charge modifying additives in the ceria suspension on the deposit microstructure has been studied. Mechanism of charging in the non-aqueous medium to modify the surface properties of the suspended particles has been discussed. 相似文献
282.
A miniaturized dual‐band C‐shaped dielectric resonator antenna (DRA) with partial ground plane is presented for IEEE 802.16d fixed WiMAX applications at 3.5 and 5.8 GHz. The design starts with dimensioning a single band cylindrical DRA, which has been transferred to get a dual‐band ring‐shaped DRA. One portion of the ring‐shaped DRA is removed for forming a C‐shaped DRA to get a more compact antenna. For easy fabrication, the compact DRA dimensioned as 60 × 50 × 6.6 mm3 is excited by a microstrip line feeding. The design parameters are inner and outer radii of the C‐shaped antenna and air gap (between DR and ground) to control both the resonating frequency and the quality factor. The result shows peak gain around 3.26 and 5.55 dBi at 3.5 and 5.8 GHz, respectively. The obtained results indicate very good agreement between the simulated and measured results. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE 22: 682–689, 2012. 相似文献
283.
This paper describes the DocMIR system which captures, analyzes and indexes automatically meetings, conferences, lectures, etc. by taking advantage of the
documents projected (e.g. slideshows, budget tables, figures, etc.) during the events. For instance, the system can automatically
apply the above-mentioned procedures to a lecture and automatically index the event according to the presented slides and
their contents. For indexing, the system requires neither specific software installed on the presenter’s computer nor any
conscious intervention of the speaker throughout the presentation. The only material required by the system is the electronic
presentation file of the speaker. Even if not provided, the system would temporally segment the presentation and offer a simple
storyboard-like browsing interface. The system runs on several capture boxes connected to cameras and microphones that records
events, synchronously. Once the recording is over, indexing is automatically performed by analyzing the content of the captured
video containing projected documents and detects the scene changes, identifies the documents, computes their duration and
extracts their textual content. Each of the captured images is identified from a repository containing all original electronic
documents, captured audio–visual data and metadata created during post-production. The identification is based on documents’
signatures, which hierarchically structure features from both layout structure and color distributions of the document images.
Video segments are finally enriched with textual content of the identified original documents, which further facilitate the
query and retrieval without using OCR. The signature-based indexing method proposed in this article is robust and works with
low-resolution images and can be applied to several other applications including real-time document recognition, multimedia
IR and augmented reality systems.
相似文献
Rolf IngoldEmail: |
284.
The polymerization kinetics of methyl methacrylate (MMA) was studied, using Tl(III)‐cyclohexanone (CH) redox system as initiator, in the presence of emulsifier [i.e., sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), and thallium triacetate (TX‐100)] over a temperature range of 25–45°C. The effect of various concentrations of MMA, Tl(III), cyclohexanone, H+, and varying ionic strengths on the rate of polymerization, rate of Tl(III) consumption (?RTl), and the percentage of monomer conversion were examined in the presence of 0.015M SDS. The kinetic results of polymerization in the absence and presence of 0.015M SDS were compared in terms of overall activation energy (Ea) for the process. The viscosity‐average molecular weight (MV) of the polymers, obtained in the presence of varying concentrations of anionic surfactant (SDS), was also determined. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2480–2485, 2004 相似文献
285.
Understanding dynamic behavior of carbon nanotubes has been of interest to researchers because of its practical applications. Recent studies show that nonlocal elasticity theory gives better results in the vibration of carbon nanotubes. The necessity of nonlocal elasticity theory, calibration of nonlocal parameter and application of nonlocal elasticity theory in various studies related to vibration of carbon nanotubes are discussed. This review emphasizes the application of nonlocal elasticity theory in the vibration of carbon nanotubes considering various types of complicating effects, nonlinearity, functionally graded material and different beam theories. 相似文献
286.
Microstresses developed in the crystallites of polymeric material due to irradiation of high-energy particle causes peak broadening
and shifting of X-ray diffraction lines to lower angle. Neutron irradiation significantly changes the material properties
by displacement of lattice atoms and the generation of helium and hydrogen by nuclear transmutation. Another important aspect
of neutron irradiation is that the fast neutron can produce dense ionization at deep levels in the materials. The polyethylene
terephthalate (PET) fibre of raw denier value, 78.2, were irradiated by fast neutron of energy, 4.44 MeV, at different fluences
ranging from 1×109 n/cm2 to 1 × 1012 n/cm2. In the present work, the radiation heating microstresses developed in PET micro-crystallites was investigated applying X’Pert-MPD
Philips Analytical X-ray diffractometer and the effects of microstresses in tensile strength of fibre measured by Instron
have also been reported. The shift of 0.45 cm−1 in the Raman peak position of 1614.65 cm{−1} to a higher value confirmed the development of microstresses due to neutron irradiation using micro-Raman technique. The
defects due to irradiation were observed by SEM micrographs of single fibre for virgin and all irradiated samples. 相似文献
287.
Abhisek Choudhary Swadesh K. Pratihar Ashish K. Agrawal Shantanu K. Behera 《Advanced Engineering Materials》2018,20(3)
288.
Sukanti Behera Vinayak B Kamble Satish Vitta Arun M Umarji C Shivakumara 《Bulletin of Materials Science》2017,40(7):1291-1299
Monovalent ion doped lanthanum cobaltate \(\hbox {La}_{1-x}\hbox {Na}_{x}\hbox {CoO}_{3 }\) (\(0 \le x \le 0.25\)) compositions were synthesized by the nitrate–citrate gel combustion method. All the heat treatments were limited to below 1123 K, in order to retain the Na stoichiometry. Structural parameters for all the compounds were confirmed by the Rietveld refinement method using powder X-ray diffraction (XRD) data and exhibit the rhombhohedral crystal structure with space group R-3c (No. 167). The scanning electron microscopy study reveals that the particles are spherical in shape and sizes, in the range of 0.2–0.5 \(\upmu \)m. High temperature electrical resistivity, Seebeck coefficient and thermal conductivity measurements were performed on the high density hot pressed pellets in the temperature range of 300–800 K, which exhibit p-type conductivity of pristine and doped compositions. The X-ray photoelectron spectroscopy (XPS) studies confirm the monotonous increase in \(\hbox {Co}^{4+}\) with doping concentration up to \(x = 0.15\), which is correlated with the electrical resistivity and Seebeck coefficient values of the samples. The highest power factor of \(10~\upmu \hbox {W~mK}^{-2 }\) is achieved for 10 at% Na content at 600 K. Thermoelectric figure of merit is estimated to be \({\sim }1 \times 10^{-2}\) at 780 K for 15 at% Na-doped samples. 相似文献
289.
Measurements of integral enthalpies of mixing of Bi–In system have been taken at 767, 813 and 855 K by a drop calorimeter over the entire composition range. Bismuth was used as the base metal, and indium was dropped by motorized dropping device. Calibration of the calorimeter was done by dropping four pieces of α-Al2O3 at the drop temperatures. The measured enthalpies of mixing are plotted against indium composition and found exothermic in nature for all the compositions. The minimum enthalpies were observed in the range of compositions xIn?~?0.40–0.50. A slight temperature dependency of enthalpy was observed for each composition. The experimental data were used to determine the binary interaction parameters using Redlich–Kister polynomial at 767, 813 and 855 K. 相似文献
290.
Electroencephalography (EEG), helps to analyze the neuronal activity of a human brain in the form of electrical signals with high temporal resolution in the millisecond range. To extract clean clinical information from EEG signals, it is essential to remove unwanted artifacts that are due to different causes including at the time of acquisition. In this piece of work, the authors considered the EEG signal contaminated with Electrocardiogram (ECG) artifacts that occurs mostly in cardiac patients. The clean EEG is taken from the openly available Mendeley database whereas the ECG signal is collected from the Physionet database to create artifacts in the EEG signal and verify the proposed algorithm. Being the artifactual signal is non-linear and non-stationary the Random Vector Functional Link Network (RVFLN) model is used in this case. The Machine Learning approach has taken a leading role in every field of current research and RVFLN is one of them. For the proof of adaptive nature, the model is designed with EEG as a reference and artifactual EEG as input. The peaks of ECG signals are evaluated for artifact estimation as the amplitude is higher than the EEG signal. To vary the weight and reduce the error, an exponentially weighted Recursive Least Square(RLS) algorithm is used to design the adaptive filter with the novel RVFLN model. The random vectors are considered in this model with a radial basis function to satisfy the required signal experimentation. It is found that the result is excellent in terms of Mean Square Error (MSE), Normalized Mean Square Error (NMSE), Relative Error (RE), Gain in Signal to Artifact Ratio (GSAR), Signal Noise Ratio(SNR), Information Quantity (IQ), and Improvement in Normalized Power Spectrum (INPS). Also, the proposed method is compared with the earlier methods to show its efficacy. 相似文献