1,630 research outputs found
Density of states of the binary alloy in the coherent potential approximation
The density of states of an electron in a binary alloy in the tight binding model is calculated in the single site coherent potential approximation (CPA) as a function of the concentration and the site energy difference. The fluctuations in the site energies due to the random environment is taken into account approximately by giving width to the site energy probability distribution function, which is normally a sum of two delta functions with proper weight factor. © 1975 the Indian Academy of Sciences
Central Pivot Heuristics for Botnet Attack Defense in Iot
Botnet assaults on IoT systems have become a big issue, and several strategies for botnet protection have been investigated by the academic and industry communities. While many of these methods are practical and effective for botnet attack prevention, one of the important limits is the load factor on the servers that manage monitoring and control in addition to catering to client system requests. To address load factor difficulties, the focus of this study report is on the conditions of installing a four-layer security control system based on the notion of central pivot points. Inspired by the effective and systematic Markov Chains concept, this publication proposes a four-layer filtering model that shows if botnet detection and prevention methods for servers are required. The model's simulated experimental study demonstrates the potential scope of deploying the system. The study also highlights the future possibilities of model improvisation that can reduce any erroneous signal production that is judged necessary
Analgorithmic Framework for Automatic Detection and Tracking Moving Point Targets in IR Image Sequences
Imaging sensors operating in infrared (IR) region of electromagnetic spectrum are gaining importance in airborne automatic target recognition (ATR) applications due to their passive nature of operation. IR imaging sensors exploit the unintended IR radiation emitted by the targets of interest for detection. The ATR systems based on the passive IR imaging sensors employ a set of signal processing algorithms for processing the image information in real-time. The real-time execution of signal processing algorithms provides the sufficient reaction time to the platform carrying ATR system to react upon the target of interest. These set of algorithms include detection, tracking, and classification of low-contrast, small sized-targets. Paper explained a signal processing framework developed to detect and track moving point targets from the acquired IR image sequences in real-time.Defence Science Journal, Vol. 65, No. 3, May 2015, pp.208-213, DOI: http://dx.doi.org/10.14429/dsj.65.816
Edge Currents in Non-commutative Chern-Simons Theory from a New Matrix Model
This paper discusses the formulation of the non-commutative Chern-Simons (CS)
theory where the spatial slice, an infinite strip, is a manifold with
boundaries. As standard star products are not correct for such manifolds, the
standard non-commutative CS theory is not also appropriate here. Instead we
formulate a new finite-dimensional matrix CS model as an approximation to the
CS theory on the strip. A work which has points of contact with ours is due to
Lizzi, Vitale and Zampini where the authors obtain a description for the fuzzy
disc. The gauge fields in our approach are operators supported on a subspace of
finite dimension N+\eta of the Hilbert space of eigenstates of a simple
harmonic oscillator with N, \eta \in Z^+ and N \neq 0. This oscillator is
associated with the underlying Moyal plane. The resultant matrix CS theory has
a fuzzy edge. It becomes the required sharp edge when N and \eta goes to
infinity in a suitable sense. The non-commutative CS theory on the strip is
defined by this limiting procedure. After performing the canonical constraint
analysis of the matrix theory, we find that there are edge observables in the
theory generating a Lie algebra with properties similar to that of a
non-abelian Kac-Moody algebra. Our study shows that there are (\eta+1)^2
abelian charges (observables) given by the matrix elements (\cal A_i)_{N-1 N-1}
and (\cal A_i)_{nm} (where n or m \geq N) of the gauge fields, that obey
certain standard canonical commutation relations. In addition, the theory
contains three unique non-abelian charges, localized near the N^th level. We
show that all non-abelian edge observables except these three can be
constructed from the abelian charges above. Using the results of this analysis
we discuss the large N and \eta limit.Comment: LaTeX, 16 pages and 2 figures. Comments added in sections 4 and 5. A
minor error corrected in section 4. Figures replaced for clarity. Typos
correcte
Advanced Mission Management System for Unmanned Aerial Vehicles
The paper presents advanced mission management system (MMS) for unmanned aerial vehicles, based on integrated modular avionics (IMA) architecture. IMA architecture enables the MMS to host high end functions for autonomous navigation and attack. MMS is a collection of systems to execute the mission objectives. The system constitutes mission computer (MC), sensors and other sub-systems. The MMS-MC needs to execute advanced algorithms like terrain referenced navigation, vision-aided navigation, automatic target recognition, sensor fusion, online path planning, and tactical planning for autonomy and safety. This demands high-end architecture in terms of hardware, software, and communication. The MMS-MC is designed to exploit the benefits of IMA concepts such as open system architecture, hardware and software architecture catering for portability, technology transparency, scalability, system reconfigurability and fault tolerance. This paper investigates on advanced navigation methods for augmenting INS with terrain-referenced navigation and vision-aided navigation during GPS non-availability. This paper also includes approach to implement these methods and simulation results are provided accordingly, and also discusses in a limited way, the approach for implementing online path planning.Defence Science Journal, Vol. 64, No. 5, September 2014, pp.438-444, DOI:http://dx.doi.org/10.14429/dsj.64.599
Assessment of genetic variability among rabbit breeds by random amplified polymorphic DNA (RAPD)-PCR
[EN] Random amplified polymorphic DNA (RAPD) technique was employed to assess the genetic variation and phylogenetic relationship among three broiler rabbit breeds. Ten individuals from each rabbit breed viz. White Giant (WG), Soviet Chinchilla (SC) and Grey Giant (GG) was taken for the study. Initially, 40 RAPD primers were screened, of which six primers were found polymorphic and they were further utilized to assess the genetic variability among these breeds. The band sharing frequencies (BSF) were computed within and between breeds. The overall BSF value within breed was highest in WG (0.846±0.02) and GG (0.846±0.01), while lowest in SC (0.818±0.02). However, between breeds, BSF value was found higher in SC-GG (0.805± 0.01) followed by WG-SC (0.792±0.02) and WG-GG (0.790±0.02). Overall, there was no significant difference (P>0.05) in BSF values within and between breeds. The BSF value indicated low genetic variability within the breed as compared to between breeds. The Nei's genetic distance (D) was found highest between WG-GG (D=0.1605) followed by WG-SC (D=0.1403) and SC-GG (D=0.1295). The phylogenetic relationship among breeds was analyzed and dendrogram revealed that SC and GG are more closer, while WG-GG are distant to each other. The study suggests that RAPD can be successfully utilized for detecting genetic variation among rabbit breeds.Rangoju, P.; Kumar, S.; Kolte, A.; Gulyani, R.; Singh, V. (2007). Assessment of genetic variability among rabbit breeds by random amplified polymorphic DNA (RAPD)-PCR. World Rabbit Science. 15(1):3-8. doi:10.4995/wrs.2007.6113815
Estimation of Compressional Wave Speed in Marine Sediments using Biot Stoll Model and Buckinghams Grain shearing Model
Acoustic properties of seafloor sediments can be estimated using theoretical models by giving geophysical properties of sediments as inputs to the respective models. Empirical relations connecting the geophysical and geoacoustic properties are available in literature. In this study an experimental assessment of two such theoretical models viz., Biot-Stoll model (BSM), a poro-elastic model and the Buckingham’s grain shearing (GS) model, a visco-elastic model is done by estimating the compressional wave speed. Compressional wave speed is measured using in-house developed sediment velocimeter and is compared with the speed estimated using both the models and a regression analysis was done. It was observed that the Coefficient of determination R2 for BSM and GS model are 0.769 and 0.729, respectively. It shows that once the constants used in GS model are evaluated for the Indian waters, then it can be used to estimate the acoustic properties of sediments
Note On Linear Stability of Steady Hydromagetic Flows of An Incompressible Fluid
In the present paper energy method is used to obtain two sufficient conditions for linear stability of steady hydrodynamical flows. The idea of the method is to construct a small three-dimensional perturbations and formulate the stability criteria for the steady magnetohydrodynamic flows of an ideal incompressible.The stability conditions so obtained ensure non existence of perturbations which grow with time faster than linealy
In-Situ Growth of Metal Oxide Nanoparticles on Cellulose Nanofibrils for Dye Removal and Antimicrobial Applications
In-Situ Growth of Metal Oxide Nanoparticles on Cellulose Nanofibrils for Dye Removal and Antimicrobial Applications
Nanocellulose is known to act as a platform for the in-situ formation of metal oxide nanoparticles, where the multiple components of the resultant hybrids act synergistically toward specific applications. However, typical mineralization reactions require hydrothermal conditions or addition of further reducing agents. Herein, we demonstrate that carboxylated cellulose nanofibril-based films can spontaneously grow functional metal oxide nanoparticles during the adsorption of heavy metal ions from water, without the need of any further chemicals or temperature. Despite the apparent universality of this behavior with different metal ions, this work focuses on studying the in-situ formation of copper oxide nanoparticles on TOCNF films as well as the resultant hybrid films with improved functionality toward dye removal from water and antimicrobial activity. Using a combination of cutting-edge techniques (e.g., in-situ SAXS and QCMD) to systematically follow the nanoparticle formation on the nanocellulosic films in real time, we suggest a plausible mechanism of assembly. Our results confirm that carboxylated cellulose nanofibril films act as universal substrate for the formation of metal oxide nanoparticles, and thus hybrid nanomaterials, during metal ion adsorption processes. This phenomenon enables the upcycling of nanocellulosic materials through multistage applications, thus increasing its sustainability and efficiency in terms of an optimal use of resources
- …