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11.
Sambit Bakshi Pankaj K. Sa Haoxiang Wang Soubhagya Sankar Barpanda Banshidhar Majhi 《Multimedia Tools and Applications》2018,77(14):17595-17623
To ensure highest security in handheld devices, biometric authentication has emerged as a reliable methodology. Deployment of mobile biometric authentication struggles due to computational complexity. For a fast response from a mobile biometric authentication method, it is desired that the feature extraction and matching should take least time. In this article, the periocular region captured through frontal camera of a mobile device is considered under investigation for its suitability to produce a reduced feature that takes least time for feature extraction and matching. A recently developed feature Phase Intensive Local Pattern (PILP) is subjected to reduction giving birth to a feature termed as Reduced PILP (R-PILP), which yields a matching time speed-up of 1.56 times while the vector is 20% reduced without much loss in authentication accuracy. The same is supported by experiment on four publicly available databases. The performance is also compared with one global feature: Phase Intensive Global Pattern, and three local features: Scale Invariant Feature Transform, Speeded-up Robust Features, and PILP. The amount of reduction can be varied with the requirement of the system. The amount of reduction and the performance of the system bears a trade-off. Proposed R-PILP attempts to make periocular suitable for mobile devices. 相似文献
12.
P. Monash Abhijit Majhi Dr G. Pugazhenthi 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2010,85(4):545-554
BACKGROUND: Ceramic membranes have received more attention than polymeric membranes for the separation and purification of bio‐products owing to their superior chemical, mechanical and thermal properties. Commercially available ceramic membranes are too expensive. This could be overcome by fabricating membranes using low‐cost raw materials. The aim of this work is to fabricate a low‐cost γ‐Al2O3–clay composite membrane and evaluate its potential for the separation of bovine serum albumin (BSA) as a function of pH, feed concentration and applied pressure. To achieve this, the membrane support is prepared using low‐cost clay mixtures instead of very expensive alumina, zirconia and titania materials. The cost of the membrane can be further reduced by preparing a γ‐alumina surface layer on the clay support using boehmite sol synthesized from inexpensive aluminium chloride instead of expensive aluminium alkoxide using a dip‐coating technique. RESULTS: The pore size distribution of the γ‐Al2O3‐clay composite membrane varied from 5.4–13.6 nm. The membrane was prepared using stable boehmite sol of narrow particle size distribution and mean particle size 30.9 nm. Scanning electron microscopy confirmed that the surface of the γ‐Al2O3–clay composite membrane is defect‐free. The pure water permeability of the support and the composite membrane were found to be 4.838 × 10?6 and 2.357 × 10?7 m3 m?2 s?1 kPa?1, respectively. The maximum rejection of BSA protein was found to be 95%. It was observed that the separation performance of the membrane in terms of flux and rejection strongly depends on the electrostatic interaction between the protein and charged membrane. CONCLUSION: The successively prepared γ‐Al2O3‐clay composite membrane proved to possess good potential for the separation of BSA with high yield and could be employed as a low cost alternate to expensive ceramic membranes. Copyright © 2009 Society of Chemical Industry 相似文献
13.
Babita Gupta A. Kapoor R. M. Mehra Tetsuo Soga Takashi Jimbo Masayoshi Umeno 《Solar Energy Materials & Solar Cells》2003,79(3):305-311
Amorphous carbon (a-C) is a potential material for the development of low-cost and high-efficiency solar cell. We report the study of the influence of light soaking up to 100 h on n-C/p-Si heterojunction solar cell. It is observed that the deterioration in the fill factor and the efficiency are significantly smaller as compared to that observed in a-Si:H solar cell. Variations in the temperature coefficients of the I–V characteristics subjected to light degradation and recovery has also been investigated. A good correlation between change in the temperature coefficient and the degradation/recovery state of cell's conversion efficiency has been observed. 相似文献
14.
Ganapati Panda Pyari Mohan Pradhan Babita Majhi 《Expert systems with applications》2011,38(10):12671-12683
Conventional derivative based learning rule poses stability problem when used in adaptive identification of infinite impulse response (IIR) systems. In addition the performance of these methods substantially deteriorates when reduced order adaptive models are used for such identification. In this paper the IIR system identification task is formulated as an optimization problem and a recently introduced cat swarm optimization (CSO) is used to develop a new population based learning rule for the model. Both actual and reduced order identification of few benchmarked IIR plants is carried out through simulation study. The results demonstrate superior identification performance of the new method compared to that achieved by genetic algorithm (GA) and particle swarm optimization (PSO) based identification. 相似文献
15.
Low Reynolds number parabolic shear flow past a circular cylinder, placed asymetrically with its centre at a distance from the shear axis, is investigated employing matching technique. The analysis of flow separation indicates coalescion of wakes with increasing . The drag is governed by a parameter λ which changes sign depending on the magnitude of , while the torque is proportional to . The case of a rotating cylinder including free rotation is also discussed. 相似文献
16.
In this paper, identification of stable and unstable first order, second order overdamped and underdamped process dynamics with time delay is presented. Relay with hysteresis is used to induce a limit cycle output and using this information, unknown process model parameters are estimated. State space based generalized analytical expressions are derived to achieve accurate results. To show the performance of the proposed method expressions are also derived for systems with a zero. In real time systems, measurement noise is an important issue during identification of process dynamics. A relay with hysteresis reduces the effect of measurement noise, in addition a new multiloop control strategy is proposed to recover the original limit cycle. Simulation results are included to validate the effectiveness of the proposed method. 相似文献
17.
Summary Axisymmetric parabolic shear flow past a spinning sphere in an unbounded viscous medium is considered using the matching technique and taking the non-uniform shear as the dominant feature, where the Reynolds number based on parabolic shearR
e
1 and the rotational Reynolds number based on the angular rotation of the sphereR
01 are such thatR
0
2/R
e
=O(1). Forces on the body are calculated and flow separation from the boundary is studied. Coalescion of two wakes or detachment of a wake into two are observed, depending on the increase in magnitudeU of the free stream for a fixedR
0
2/R
e
or increase inR
0
2/R
e
for a fixedU respectively.With 8 Figures 相似文献
18.
Nasser A.M. Barakat K.A. Khalil Faheem A. Sheikh A.M. Omran Babita Gaihre Soeb M. Khil Hak Yong Kim 《Materials science & engineering. C, Materials for biological applications》2008,28(8):1381-1387
In the present study, subcritical water and alkaline hydrolysis methods are proposed methodologies for extraction of natural hydroxyapatite bioceramic from bovine bone. In these processes, the bovine bones powder were treated by high pressure water at 250 °C for 1 h and 25% (wt) sodium hydroxide at 250 °C for 5 h, respectively. Also the conventional calcination methodology has been utilized as well (T = 850 °C for 1 h). The obtained apatites from the three treatment processes have been characterized by powder X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FT IR), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), electron scanning microscopy (SEM), energy dispersive X-ray analysis (EDX) and field emission scanning electron microscopy (FE SEM). FT IR and XRD results affirmed that both the proposed methods and the traditional one can eliminate the collagen and other organic materials present in the bovine bones. The physiochemical characterizations for the obtained apatites have proved that the subcritical water and the alkaline hydrolysis relatively preserve the carbonate content present in the biological apatite, so they yield carbonated hydroxyapatite which is medically preferable. While, the thermal process produces almost hydroxyapatite carbonate-free. 相似文献
19.
Hydrogeochemistry,Elemental Flux,and Quality Assessment of Mine Water in the Pootkee-Balihari Mining Area,Jharia Coalfield,India 总被引:3,自引:0,他引:3
Abhay?Kumar?SinghEmail author Mukesh?K.?Mahato Babita?Neogi G.?C.?Mondal T.?B.?Singh 《Mine Water and the Environment》2011,30(3):197-207
Ninety nine mine water discharge samples were collected and analyzed for pH, electrical conductivity (EC), major cations,
anions, and trace metals in the Pootkee-Balihari coal mining area of the Jharia coalfield. The mines of the area annually
discharge 34.80 × 106 m3 of mine water and 39,099 t of solute loads. The pH of the analyzed mine waters ranged from 6.97 to 8.62. EC values ranged
from 711 μS cm−1 to 1862 μS cm−1, and reflect variations in lithology, geochemical processes, and hydrological regimes in the mines. The cation and anion
chemistry indicate the general ionic abundance as: Mg2+ > Ca2+ > Na+ > K+ and HCO3
− > SO4
2− > Cl− > NO3
− > F−, respectively. Elevated SO4
2− concentrations in the Gopalichuck, Kendwadih, and Kachhi-Balihari mine waters are attributed to pyrite weathering. The water
quality assessment indicated that TDS, hardness, Mg2+, and SO4
2− are the major parameters of concern in the study area. Except for Fe, all of the measured metals in the mine water were well
within the levels recommended for drinking water. With only a few exceptions, the mine water is of good to permissible quality
and suitable for irrigation. 相似文献
20.