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401.
Review of background subtraction methods using Gaussian mixture model for video surveillance systems
Foreground detection or moving object detection is a fundamental and critical task in video surveillance systems. Background subtraction using Gaussian Mixture Model (GMM) is a widely used approach for foreground detection. Many improvements have been proposed over the original GMM developed by Stauffer and Grimson (IEEE Computer Society conference on computer vision and pattern recognition, vol 2, Los Alamitos, pp 246–252, 1999. doi: 10.1109/CVPR.1999.784637) to accommodate various challenges experienced in video surveillance systems. This paper presents a review of various background subtraction algorithms based on GMM and compares them on the basis of quantitative evaluation metrics. Their performance analysis is also presented to determine the most appropriate background subtraction algorithm for the specific application or scenario of video surveillance systems. 相似文献
402.
403.
In the recently published article cited above, the author's name Aishwarya Jyoti was incorrectly printed. The correct author's name is published above. 相似文献
404.
Saurabh Jyoti Sarma Satinder Kaur Brar Yann Le Bihan Gerardo Buelna Louhichi Rabeb Carlos Ricardo Soccol Mhamdi Naceur Bouraoui Rachid 《International Journal of Hydrogen Energy》2013
Crude glycerol (CG) has several advantages over a range of conventional substrates used for biohydrogen production by Enterobacter aerogenes NRRL B 407. Meanwhile, high process cost due to requirement of expensive supplementary media component is a concern. Therefore, different less expensive (or wastes) materials have been evaluated as supplementary nutrient for H2 production by CG (meat processing and restaurant waste based biodiesel derived) bioconversion. Among the materials selected, slaughterhouse liquid waste (SL), brewery waste biomass (BWB) and urea was found to improve the production by 18.81 ± 3.56, 27.30 ± 3.54 and 38.57 ± 3.66%, respectively. Further, in the case of urea (10 mg/L), cumulative production as high as 116.41 ± 3.72 mmol H2/L media has been achieved; which is comparable to other reports available on CG bioconversion. Thus, present study demonstrates successful replacement of large amount (∼5–6 g/L) of expensive nutrients/buffering agents by negligible amount (∼10 mg/L) of different waste materials, without compromising the cumulative H2 yield. Further, the strain used in the present study was found to grow at an acidic pH as low as 3.3, indicating its prospective application for dark fermentative H2 production. 相似文献
405.
406.
Arup Jyoti Das Gitashree Das Tatsuro Miyaji 《International Journal of Food Properties》2016,19(3):636-651
The purified phenolic extracts of Artocarpus heterophyllus, Oldenlandia corymbosa, Cyclosorus extensa, and Alpinia malaccensis were tested for the presence of various polyphenols and antioxidant activities. The polyphenols were extracted with ethanol and purified by stepwise dialysis and column elution. High-performance liquid chromatography was performed to detect and quantitate the polyphenols and 10 different in vitro methodologies were used to measure antioxidant properties. Quercetin, ferulic acid, and salicylic acid were present in all the species. Chlorogenic and p-coumaric acid in A. heterophyllus; p-coumaric acid, caffeic acid, naringin, catechol, and resorcinol in C. extensa; chlorogenic, caffeic, and quinic acid in O. corymbosa and naringin, quinic acid and catechol in A. malaccensis were detected with varied concentrations. The 2-deoxyribose, 1,1-diphenyl-2-picryl-hydrazyl and 2,2’-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) assays exhibited high radical scavenging activities and they were also able to combat ?OH radicals and H2O2 to an extent of 25.53 and 71.23% respectively. Superoxide anions and nitric oxide radicals were scavenged up to 63.85 and 56.24%, respectively, and the extracts exhibited ferric ions chelation and ferrous ions reduction capacity. A reduction in the level of lipid peroxidation was also observed. All four species were found to be potent sources of polyphenols having antioxidative property. The results fully justified the use of these plants in the beer making process of Assam, India. 相似文献
407.
408.
Parampaul K. Banipal Jyoti Sharma Pallavi Sohal Tarlok S. Banipal 《Journal of surfactants and detergents》2021,24(2):229-242
We have examined the mixed micellar behavior of {amphiphilic drug; chlorpromazine hydrochloride (CPZ) + cationic surfactant; cetyltrimethylammonium bromide (CTAB)} at varying mole fractions of CPZ (αCPZ = 0.2, 0.4, 0.6, and 0.8) in (0.1, 0.3, and 0.5) mol kg−1 glycine(aq) solutions at 298.15, 308.15, and 318.15 K, by using conductometric, volumetric, isentropic compressibility, UV–visible absorbance, fluorescence, and dynamic light scattering (DLS) techniques. The critical micelle concentration (CMC) values obtained from above measurements have been utilized to calculate the thermodynamic parameters (ΔG°m, ΔH°m, and ΔS°m) and degree of ionization (α) at studied temperatures and concentrations. The partial specific volume (φv), partial specific isentropic compression (φκ), and isentropic compressibility (κs) have been calculated from the experimental density and speed of sound measurements and the results have been used to elucidate different interactions occurring in these systems. These results are further supported by UV–visible absorbance and fluorescence spectroscopic studies. The hydrodynamic diameters (Dh) of the mixed micellar system have been measured from the DLS studies. Thermodynamic and spectroscopic studies depict the dominance of hydrophobic/hydrophilic-hydrophobic interactions between the alkyl (R = C16H33) chain of CTAB or hydrophobic tricyclic scaffolding of CPZ/Br−/N+-CH3 group of CTAB or hydrophilic group i.e., tertiary amine portion of CPZ with hydrophobic group of glycine. 相似文献
409.
Jyoti Rani Varun K. Kushwaha Jayant Kolte Chakkalakal V. Tomy 《Journal of the American Ceramic Society》2018,101(12):5651-5658
Polycrystalline bilayer thin film of multiferroic [Ba(Zr0.2Ti0.8)O3‐0.5(Ba0.7Ca0.3)TiO3]/CoFe2O4([BZT‐0.5BCT]/CFO) has been deposited on Pt/Si (100) substrate using a pulsed laser deposition technique. The dielectric analysis reveals a significant change in the dielectric constant (~39% at a typical frequency of 100 Hz) at room temperature when a magnetic field is applied, in addition to a substantial improvement in the saturation polarization. A low leakage current density (~ 5 × 10?7 A/cm2) and a high magnetoelectric coupling coefficient (αE) both in the transverse (~2.085 V/Oe cm) as well as in the longitudinal (~0.708 V/cm Oe) directions, indicate in‐principle usability of this system for multifunctional device applications in thin film form. 相似文献
410.
Mandeep Dalal Sangeeta Chahar Jyoti Dalal Rekha Devi Dinesh Kumar Sushma Devi V.B. Taxak Avni Khatkar Mukesh Kumar S.P. Khatkar 《Ceramics International》2018,44(9):10531-10538
Metal nitrates are used to synthesize a series of novel Ba2Y1-xV3O11:xSm3+ nanophosphors via urea-assisted solution combustion route. X-ray diffraction (XRD), diffuse reflectance (DR), transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy were employed to analyse the structure, morphology, photoluminescent behaviour and energy transfer mechanism. Rietveld analysis over Ba2Y0.98Sm0.02V3O11 showed that Y3+ ions can be well-replaced by trivalent samarium ions without resulting any major alteration in the crystal structure of host lattice. Furthermore, the lattice parameters were determined for both the host as well as the doped composition. The Scherrer equation yielded an average particle size of 44?nm, which in turn was further confirmed by TEM micrographs. The optical band-gap of the host (3.92?eV) was calculated from the diffuse reflectance spectra. Moreover, the photoluminescence spectral studies showed that under near ultra-violet (NUV) excitation of 340?nm, our nanophosphor powder exhibits the characteristic emission peaks of trivalent samarium along with the emission of VO43? (501?nm) group. The excitation energy transfer from vanadate group to Sm3+ produced a systematic color tunablity in white region itself. The optimum Sm3+ concentration for better luminescence was found to be 2?mol%. The critical distance for energy transfer was calculated to be 29.02?Å, which in turn assisted to shortlist the mechanism responsible for luminescence-quenching (dipole-dipole) arising from the over-doping of the activator. The photoluminescence decay curves revealed the decay kinetics of 4G5/2 electronic state. Finally, the calculation of CIE color coordinates from emission spectra in MATLAB program unveiled a somewhat white-light emitter which may find potential applications in phosphor-converted white light emitting diodes (PC-WLED) under near-ultraviolet (NUV) excitation. 相似文献