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排序方式: 共有529条查询结果,搜索用时 15 毫秒
51.
Aditya Abhyankar Author Vitae Stephanie Schuckers Author Vitae 《Pattern recognition》2010,43(3):987-1007
One important category of non-ideal conditions for iris recognition is off-angle iris images. Practically it is very difficult for images to be captured with no offset. It then becomes necessary to account for off angle information in order to maintain robust performance. A biorthogonal wavelet based iris recognition system, previously designed at our lab, is modified and demonstrated to perform off-angle iris recognition. Biorthogonal wavelet network (BWN) are developed and trained for each class. The non-ideal factors are adjusted by repositioning the BWN. To test, along with the real data, synthetic iris images are generated by using affine and geometric transforms of 0°, 10° and 20° experimentally collected images. The tests were carried out on the experimentally collected off-angle data and synthetically generated data for angles from 0° to 60° with a resolution of 5°. This approach is shown to have less constraints than a transformation based iris recognition approach. Iris images off-angle by up to 42° for synthetic data and up to 45° for experimental data are successfully recognized. 相似文献
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53.
Ahmad Khusro Mohammad S. Hashmi Abdul Quaiyum Ansari Aditya Mishra Mohammad Tarique 《International Journal of Circuit Theory and Applications》2019,47(6):941-953
In this paper, development of a small signal model for 2 × 200 μm GaN HEMT based on the conventional 20-element model is presented. The proposed model presents a direct parameter extraction algorithm, instead of the hybrid optimization approach, that provides simplification, accuracy, and less computational complexity. The extrinsic elements are extracted using a modified cold pinch-off condition while discarding the unwanted forward biasing of the gate. The negative drain to source capacitance Cds is also observed in the ohmic region (for smaller VDS). An excellent agreement found between the measured and modeled data for a wide range of frequencies and bias values shows the effectiveness of the proposed approach. The proposed modeling technique is validated with a good agreement between the achieved bias dependency of intrinsic parameter values and the respective theoretical parameter values. 相似文献
54.
Nano-sized light rare-earth (La, Pr, Nd, and Sm) doped Ba0.90Ca0.10Ti0.90Zr0.10O3 ceramics were synthesized to enhance the energy storage performance. The Rietveld study of bare and doped samples has shown tetragonal crystal symmetry and a single-phase perovskite structure. The rare-earth addition in Ba0.90Ca0.10Ti0.90Zr0.10O3 has resulted in a remarkable change in the microstructure of the doped samples. The addition of Nd in Ba0.90Ca0.10Ti0.90Zr0.10O3 lattice has resulted in optimum grain size and density among the five compositions. As a result of improvement in morphological characteristics in the Nd-doped sample, the dielectric, ferroelectric and piezoelectric characteristics were significantly enhanced. The Nd-doped sample has shown a relaxor behavior with a maximum dielectric constant of 10788 combined with a high saturation polarization of 41.88 μC/cm2. Further, the material has shown optimum electromechanical behavior with excellent aging characteristics. The obtained properties of Nd-doped Ba0.90Ca0.10Ti0.90Zr0.10O3 sample justifies its potential application in multi-layer energy storage capacitors. 相似文献
55.
Aditya Arun Lakshaman Kumar Anirban Chowdhury 《Journal of the American Ceramic Society》2021,104(7):3497-3507
Dense (~97%) CaO-stabilized ZrO2 ceramic was stabilized with minimum (3 mol%) doping (reported to date) and processed via conventional sintering at a low temperature (~1200°C); compositional analysis via X-ray florescence confirmed the CaO doping accuracy. Phase-pure tetragonal structure (characterized via both X-ray diffraction and Raman spectroscopy) along with uniform nanograins (90 nm) of the ceramic ensured the evolution of no monoclinic phase even after vigorous low-temperature degradation experiments (both thermal and hydrothermal aging for 80-100 h). The sintered ceramic recorded a high hardness (~15 GPa); the indentation toughness value was also comparable to a 3 mol% yttria-stabilized zirconia system. The remarkable structure–property correlations in the 3 mol% CaO-stabilized ZrO2 ceramic suggests that the same may be worth examining for suitable future applications (e.g., in dental ceramics). 相似文献
56.
Jianjun Gao Choi Look Law Hong Wang Sheel Aditya 《Journal of Infrared, Millimeter and Terahertz Waves》2002,23(11):1611-1626
An improved equivalent circuit model under pinchoff condition for extracting parasitic model parameters for Double Heterojunction δ-doped PHEMTs is presented. Good prediction for S parameters and noise performance are obtained up to 40GHz. A modified parameter extraction technique based on this new model was use to determine a PHEMT equivalent circuit model. Signification improvements of the accuracy of S parameters are obtained by using the new pinchoff model. 相似文献
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58.
Mohammed Muhammad Zafran Raja Ng Zi Wei Putranto Aditya Kong Zong Yang Sunarso Jaka Aziz Muhammad Zein Sharif H. Giwangkara Jannata Butar Ivan 《Clean Technologies and Environmental Policy》2023,25(5):1551-1567
Clean Technologies and Environmental Policy - This study aims to propose a new process design, simulation, and techno-economic analysis of an integrated process plant that produces glucose and... 相似文献
59.
Sarkar Aditya Murty S. V. S. Narayana Prasad M. J. N. V. 《Metallurgical and Materials Transactions A》2020,51(9):4742-4752
Metallurgical and Materials Transactions A - The Cu-Cr-Zr-Ti alloy was subjected to single-hit plane strain compression tests in the temperature range of 923 K to 1073 K... 相似文献
60.
Geotextiles can be successfully employed for any geotechnical application when they are able to sustain pre-defined levels of tensile stresses. The biaxial tensile test has an advantage over other tensile test methods in that it does not allow “necking” during deformation which simulates the operational conditions of geotextiles under confined stresses. In this study, the model for uniaxial tensile behavior of nonwovens has been modified to investigate the biaxial tensile behavior of spunbonded geotextiles. The model has included the effect of fiber re-orientation, stress-strain behavior of constituent fibers, and physical characteristics of nonwovens when the geotextile specimen is laterally constrained. A comparison is made between predicted and experimental stress-strain curves obtained from previous work (Bais-Singh and Goswami, 1998). Theoretical findings of biaxial tensile behavior obtained using the layer theory are also critically discussed. In addition, it has been revealed that fiber re-orientation is a key factor in translating the random spunbonded nonwoven geotextiles to anisotropic structures under defined biaxial tensile stresses. 相似文献