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91.
Aparna Mir Dhriti Mallik Soumya Bhattacharyya Dipankar Mahata Arvind Sinha Suprabha Nayar 《Journal of materials science. Materials in medicine》2010,21(8):2365-2369
Poly (vinyl) alcohol stabilized aqueous ferrofluids (PVA-ff) were used as nanotemplates for the crystallization of calcium
hydroxyapatite (HAp). Four sets of PVA-ff-HAp nanocomposites were synthesized using 20, 40, 60 and 80 ml of PVA-ff for the
same initial constituents of HAp. Various physico-chemical analyses suggest that the HAp lattice structure accommodates PVA-ff
to a certain extent, beyond which the magnetic intra-molecular interactions predominate and PVA-ff starts to be pushed out
of the HAp matrix. The in situ incorporation of PVA-ff during HAp synthesis results in a novel magnetic biomaterial with potential
applications as targeted delivery vehicles. 相似文献
92.
Secured and Imperceptible Data Transmission Through Digital Audio Signal with Reduced Internal Noise
Wireless Personal Communications - The work proposed in this paper aims at two major concerns of wireless transmission, which are security and imperceptibility of the transmitting data. This method... 相似文献
93.
A systematic study for the flow around a row of five square cylinders placed in a side-by-side arrangement and normal to the oncoming flow at a Reynolds number of 150 is carried out through the numerical solution of the two-dimensional unsteady incompressible Navier-Stokes equations. Special attention is paid to investigate the effect of the spacing between the five cylinders on the wake structure and vortex shedding mechanism. The simulations are performed for the separation ratios (spacing to size ratio) of 1.2, 2, 3 and 4. Depending on the separation ratio the following flow patterns are observed: a flip-flopping pattern, in-phase and anti-phase synchronized pattern and non-synchronized pattern. These flow patterns are supposed to be a consequence of the interaction between two types of frequencies viz. the vortex shedding (primary) and the cylinder interaction (secondary) frequencies. At small separation ratio the flow is predominantly characterized by the jet in the gaps between successive cylinders and the secondary frequencies play a role in the resulting chaotic flow. On the contrary, at higher separation ratio the secondary frequencies almost disappear and the resulting flow becomes more synchronized dominated by the primary frequency. 相似文献
94.
Biplob Mondal Santanu Maity Sonali Das Dipankar Panda Hiranmay Saha Avra Kundu 《Microsystem Technologies》2016,22(12):2757-2764
Thin films of metal-oxide with integrated microheater on micromachined silicon substrate have attracted great deal of interest towards the development of extremely small and highly sensitive gas sensor. Fabrication of MEMS microheater which is the key component for the development of low power gas sensor is reported here. The microheater is fabricated in a novel co planer fashion where the heating element and the inter-digitated electrode are place side by side. The fabricated device is structurally and electrically characterized by SEM and I–V measurements. Using ZnO–SnO2 composite material, hydrogen sensor was constructed on the microheater platform. A suitable package for encapsulating the fabricated device is designed and the device was successfully mounted on it. The sensing behavior of the packaged sensor is performed by exposing the sensor to hydrogen. 相似文献
95.
Revisiting negative selection algorithms 总被引:4,自引:0,他引:4
This paper reviews the progress of negative selection algorithms, an anomaly/change detection approach in Artificial Immune Systems (AIS). Following its initial model, we try to identify the fundamental characteristics of this family of algorithms and summarize their diversities. There exist various elements in this method, including data representation, coverage estimate, affinity measure, and matching rules, which are discussed for different variations. The various negative selection algorithms are categorized by different criteria as well. The relationship and possible combinations with other AIS or other machine learning methods are discussed. Prospective development and applicability of negative selection algorithms and their influence on related areas are then speculated based on the discussion. 相似文献
96.
Mona Abo-Hashesh Dipankar Ghosh Alexandre Tourigny Azougui Taous Patrick C. Hallenbeck 《International Journal of Hydrogen Energy》2011,36(21):13889-13895
Photosynthetic bacteria have been extensively investigated for biohydrogen production due to their high intrinsic substrate conversion efficiency. Many studies have examined different aspects of photo fermentative hydrogen production using various volatile organic fatty acids under nitrogen limited conditions, and in some cases nearly stoichiometric hydrogen yields have been obtained. In addition, there has been great interest in using photosynthetic bacteria to increase the yields of dark fermentation of glucose through either two stage or co-culture approaches. Although these processes can achieve yields of about 7 mol of H2 per mole of glucose, there have many drawbacks. Thus, we have begun the systematic investigation of a simple one stage system for the conversion of glucose to hydrogen through photofermentation by Rhodobacter capsulatus. Yields of about 3 mol of H2 per moles of glucose have been obtained, which represents a yield of 25% yield. Thus improvement is needed and can be sought through a variety of means, including. process optimization and gene inactivation. These approaches could allow the development of a single stage process for the complete stoichiometric conversion of glucose, or glucose containing wastes, to hydrogen with a minimal lag phase and relative insensitivity to inhibition by fixed nitrogen. This would present an attractive simple alternative to either two stage or co-culture fermentations for the complete conversion of carbohydrate substrates to hydrogen. 相似文献
97.
The model for sphericosymmetric thin‐flame combustion of a multicomponent fuel droplet in a dilute spray using a unit cell approach, developed in the companion paper, has been used for studying the interaction effect between droplets. The effects of droplet spacing, ambient oxidizer concentration, ambient temperature and pressure have been considered. Droplet life increases with decrease in droplet spacing, ambient temperature and ambient oxidizer concentration. However, droplet life has a weak dependence on ambient pressure. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
98.
Vijay K. Mishra Dipankar N. Basu 《Numerical Heat Transfer, Part A: Applications》2013,63(10):1119-1135
This article deals with the analysis of combined mode conduction and radiation heat transfer in a porous medium, and simultaneous estimation of the optical properties of the porous matrix. Simultaneous solution of the gas- and solid-phase energy equations encompasses local thermal nonequilibrium, while the convective heat exchange term couples the gas- and the solid-phase energy equations. A localized uniform volumetric heat generation zone is the source of heat transfer in the porous matrix. With volumetric radiative information needed in the solid-phase energy equation computed using the discrete transfer method, the solid- and gas-phase energy equations are simultaneously solved using the finite difference method. For a given set of boundary conditions and operating parameters, the computed temperature distribution serves as the exact temperature profile necessary in the estimation of parameters. In the estimation of parameters using inverse analysis, the objective function is minimized using the genetic algorithm. Effects of measurement error, number of generations, population size, crossover probability, and mutation probability are studied in regard to the accuracy of results and the computational time required. Reasonably accurate estimations of extinction coefficient, scattering albedo, and emissivity of the porous matrix are obtained. 相似文献
99.
Dipankar Srimani Ekambaram Balaraman Boopathy Gnanaprakasam Yehoshoa Ben‐David David Milstein 《Advanced Synthesis \u0026amp; Catalysis》2012,354(13):2403-2406
Cross‐dehydrogenative coupling of primary alcohols with secondary alcohols to obtain mixed esters with the liberation of molecular hydrogen is achieved in high yield and good selectivity under neutral conditions, using a bipyridyl‐based PNN ruthenium(II) pincer catalyst. 相似文献
100.
The biological immune system is an autonomic system for self-protection, which has evolved over millions of years probably through extensive redesigning, testing, tuning and optimization process. The powerful information processing capabilities of the immune system, such as feature extraction, pattern recognition, learning, memory, and its distributive nature provide rich metaphors for its artificial counterpart. Our study focuses on building an autonomic defense system, using some immunological metaphors for information gathering, analyzing, decision making and launching threat and attack responses. This on-going research effort is not to mimic the nature but to explore and learn valuable lessons useful for self-adaptive cyber defense systems. 相似文献