Towards applying FCM with DBSCAN for Detecting DDoS Attack in Cloud Infrastructure to Improve Data Transmission Rate

Cloud is a pay-to-use technology which can be used to offer IT resources instead of buying computer hardware. It is time saving and cheaper technology. This paper analyzes the DDoS attack on cloud infrastructure and can be detected by using FCM with DBSCAN hybrid algorithm that classifies the clusters of data packets and detects the outlier in that particular data packet. The experimental outcome shows that the enhanced hybrid approach has better results in detecting the DDoS attack. The DDoS attack targets the main host of the cloud infrastructure by sending unwanted packets. This attack is a major threat to the network security. The FCM with DBSCAN hybrid approach detects outliers and also assigns one specific data point in clusters to detect DDoS attack in cloud infrastructure. By using this hybrid approach the data can be grouped as clusters and the data beyond the noise level can also be detected. This algorithm helps in identifying the data that are vulnerable to DDoS attack. This detection helps in improving the data transmission rate

Cellular Automata with Synthetic Image A Secure Image Communication with Transform Domain

    Image encryption has attained a great attention due to the necessity to safeguard confidential images. Digital documents, site images, battlefield photographs, etc. need a secure approach for sharing in an open channel. Hardware – software co-design is a better option for exploiting unique features to cipher the confidential images. Cellular automata (CA) and synthetic image influenced transform domain approach for image encryption is proposed in this paper. The digital image is initially divided into four subsections by applying integer wavelet transform. Confusion is accomplished on low – low section of the transformed image using CA rules 90 and 150. The first level of diffusion with consecutive XORing operation of image pixels is initiated by CA rule 42. A synthetic random key image is developed by extracting true random bits generated by Cyclone V field programmable gate array 5CSEMA5F31C6. This random image plays an important role in second level of diffusion. The proposed confusion and two level diffusion assisted image encryption approach has been validated through the entropy, correlation, histogram, number of pixels change rate, unified average change intensity, contrast and encryption quality analyses

Interfacial Hot Carrier Collection Controls Plasmonic Chemistry

Harnessing non-equilibrium hot carriers from plasmonic metal nanostructures constitutes a vibrant research field. It promises to enable control of activity and selectivity of photochemical reactions, especially for solar fuel generation. However, a comprehensive understanding of the interplay of plasmonic hot carrier-driven processes in metal/semiconducting heterostructures has remained elusive. In this work, we reveal the complex interdependence between plasmon excitation, hot carrier generation, transport and interfacial collection in plasmonic photocatalytic devices, uniquely determining the charge injection efficiencies at the solid/solid and solid/liquid interfaces. Interestingly, by measuring the internal quantum efficiency of ultrathin (14 to 33 nm) single-crystalline plasmonic gold (Au) nanoantenna arrays on titanium dioxide substrates, we find that the performance of the device is governed by hot hole collection at the metal/electrolyte interface. In particular, by combining a solid- and liquid-state experimental approach with ab initio simulations, we show a more efficient collection of high-energy d-band holes traveling in [111] orientation, resulting in a stronger oxidation reaction at the {111} surfaces of the nanoantenna. These results thus establish new guidelines for the design and optimization of plasmonic photocatalytic systems and optoelectronic devices

Electrochemical capacitance of CO-terminated Pt(111) dominated by the CO-solvent gap

Catalysis and Surface Chemistr

STANDARDIZATION OF A SIDDHA FORMULATION AMUKKARA CURANAM BY HPTLC

Amukkara curanam, a Siddha formulation, currently used in all types of gastric disorders, rheumatic pain, insomnia and sexual insufficiency, was investigated for the estimation of the marker compounds, withaferine A and piperine contents in a prepared standard formulation and a commercial formulation by using HPTLC method of analysis. The two formulations were subjected to methanol, ethyl acetate and chloroform extractions by using Soxhhlet apparatus The chromatogram was developed using chloroform: methanol (8.5:1.5 v/v) and toluene: ethyl acetate (7:3 v/v) as mobile phases for the estimation of withferine A and piperine respectively. The detection and quantification were performed at a wavelength of 220 nm for withaferine A and 254 nm for piperine. The linear regression analysis of calibration plots of withferine A and piperine exhibited linear relationship in the range of 5 – 15 µg and 50 – 150 ng respectively, while the % recovery was found to be 94.52% w/w of withaferine A and 98.73%w/w of piperine, thus proving the accuracy and precision of the analysis. Methanol and ethyl acetate were found to be the suitable solvents for the extraction of withaferin A and piperine respectively. The withaferine A content in standard formulation was found to be much higher in all the three extracts than that of the commercial sample. However, the piperine content in all the three extracts of standard formulation was slightly lower than the respective extracts of commercial formulation. The proposed HPTLC method was found to be rapid, simple and accurate for quantitative estimation of withferine A and piperine in different formulation extracts

Evaluation of classical precipitation descriptions for γ′′(Ni3Nb−D022) in Ni-base superalloys

The growth/coarsening kinetics of γ′′(Ni3Nb−D022) precipitates have been found by numerous researchers to show an apparent correspondence with the classical (Ostwald ripening) equation outlined by Lifshitz, Slyozov and (separately) Wagner for a diffusion controlled regime. Nevertheless, a significant disparity between the actual precipitate size distribution shape and that predicted by LSW is frequently observed in the interpretation of these results, the origin of which is unclear. Analysis of the literature indicates one likely cause for this deviation from LSW for γ′′ precipitates is the “encounter” phenomenon described by Davies et al. (Acta Metall 28(2):179–189, 1980) that is associated with secondary phases comprising a high volume fraction. Consequently, the distributions of both γ′′ precipitates described in the literature (Alloy 718) and measured in this research in Alloy 625 are analysed through employing the Lifshitz–Slyozov-Encounter-Modified (LSEM) formulation (created by Davies et al.). The results of the LSEM analysis show good far better agreement than LSW with experimental distributions after the application of a necessary correction for what is termed in this research as “directional encounter”. Moreover, the activation energy for γ′′ coarsening in Alloy 625 shows conformity with literature data once the effect of heterogeneous (on dislocations) precipitate nucleation at higher temperatures is accounted for

Modelling Clock Synchronization in the Chess gMAC WSN Protocol

We present a detailled timed automata model of the clock synchronization algorithm that is currently being used in a wireless sensor network (WSN) that has been developed by the Dutch company Chess. Using the Uppaal model checker, we establish that in certain cases a static, fully synchronized network may eventually become unsynchronized if the current algorithm is used, even in a setting with infinitesimal clock drifts

Quantum-mechanical effects in photoluminescence from thin crystalline gold films

Luminescence constitutes a unique source of insight into hot carrier processes in metals, including those in plasmonic nanostructures used for sensing and energy applications. However, being weak in nature, metal luminescence remains poorly understood, its microscopic origin strongly debated, and its potential for unravelling nanoscale carrier dynamics largely unexploited. Here, we reveal quantum-mechanical effects emanating in the luminescence from thin monocrystalline gold flakes. Specifically, we present experimental evidence, supported by first-principles simulations, to demonstrate its photoluminescence origin when exciting in the interband regime. Our model allows us to identify changes to the measured gold luminescence due to quantum-mechanical effects as the gold film thickness is reduced. Excitingly, such effects are observable in the luminescence signal from flakes up to 40 nm in thickness, associated with the out-of-plane discreteness of the electronic band structure near the Fermi level. We qualitatively reproduce the observations with first-principles modelling, thus establishing a unified description of luminescence in gold and enabling its widespread application as a probe of carrier dynamics and light-matter interactions in this material. Our study paves the way for future explorations of hot-carriers and charge-transfer dynamics in a multitude of material systems.Comment: Main text 21 pages and 4 figures. Supplemental Information 33 pages and 17 figure

Detection of short-period coronal oscillations during the total solar eclipse of 24 october, 1995

An experiment to search for short-period oscillations in the solar corona was conducted during the total solar eclipse of 1995 October 24 at Kalpi, India. The intensity in the continuum, centred around 5500 Å and with a passband having a half-width of 240 Å, was recorded at a counting rate of 20 Hz using a thermoelectric-liquid cooled photomultiplier. The power-spectrum analysis of the data reveals that most of the power is contained in 6 frequencies below 0.2 Hz. A least-square analysis gives the periods of the 6 frequency components to be 56.5, 19.5, 13.5, 8.0, 6.1, and 5.3 s. These oscillations are found to be sinusoidal, and their amplitudes are found to lie in the range 0.2-1.3% of the coronal brightness. Assuming these oscillations to be fast magnetosonic modes, the calculations indicate the availability of enough flux for the heating of the active regions in the solar corona