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Materials are indispensible but the supply is limited. In particularly, the supply of material is limited for specific applications. Light weight low strength applications are very wide. This investigation focuses the natural fibre hybrid with artificial fiber based hybrid composite preparation. The sisal and banana fibre is used to prepare the composite with glass fibre. The banana fiber is here treated with specific concentration of sodium oxidanide in the distilled water. The composites synthesized with treated and untreated banana fibres. The alternate fashion of horizontal and vertical is followed for fibres’ orientation. The bio epoxy is employed as matrix material with mix of hardener. The prepared composite are characterized by water absorbability, tensile properties, flexural properties and shock absorption capacities. The synthesized composites also characterized for dry and wet applications.

This article briefly reviews the impact of parameters, such as, angle of incidence, applied magnetic field, electron density, and thickness ratio, on the band structures of a magnetized cold plasma photonic crystal considering different sets of chosen values of these parameters. We observe a simultaneous enhancement in the two obtained photonic bandgaps with increase in the electron density as well as incident angle and there is a shifting in the band positions, where lower band edge for first wider photonic bandgap is found to be more sensitive in comparison to higher band edge. It is noticed that, on increasing the applied magnetic field strength as well as thickness ratio, the first bandgap decreases with a significant shifting in lower band edge as compared to higher band edge. However, the second narrow forbidden gap shows reverse behaviour in its width with thickness ratio. Thus, these four parameters act as controlling factors for both width and location of the photonic bands in a 1-D magnetized plasma PhC. The obtained results are also in a good agreement with those previously investigated by many researchers with such extrinsic PhCs. Hence, the article provides some important insights for designing tunable broadband reflectors in the GHz frequency regions for microwave devices.

In this novel study for the most part paying attention regarding flexural strength in addition to flexural modulus of chicken feather fiber participated fiber reinforced polyester composite. There are three different length of fiber such as 5mm, 10mm, 15mm and 20mm with three different percentage of chicken feather fiber with neat polyester produce 12 composites. The flexural strength and flexural modulus experiments were accomplished for each and every specimen and the subsequent values noted to recognize the appropriate specimen composition and corresponding length of fiber.

Dye sensitized solar cells (DSSCs), sensitized with natural coloring pigments extracted from Grapes, Beta vulgaris, Piper betel leaves and Spinach leaves were prepared. These dyes were prepared using ethanol as solvent. Different dye extracts were used as sensitizer for the photo-electrode and incorporated in the DSSCs. Photo-electrochemical performances of these DSSCs were evaluated under short circuit current (ISC) ranging from 7.5 to 2.45 mA, with open circuit voltage (VOC) ranging from 0.25 to 0.42 V and 100 mW/cm2 light intensity. Among these four different photovoltaic DSSCs, the performance of the DSSC prepared with Spinach extract as a sensitizer gave the best performance with ISC of 7.56 mA, Voc of 0.339 V, a fill factor (FF) of 0.645, and an overall solar energy conversion efficiency (η) of 1.64%.

Dye sensitized solar cells (DSSCs), sensitized with natural coloring pigments extracted from Betel leaves were prepared. The dyes from Betel leaves were prepared using ethanol as solvent. Four DSSCs were prepared, one using conventional sintering method and other three using microwave sintering method, keeping microwave power as constant and by varying exposure time. Microwave sintering was expected to increase the overall performance of the DSSCs. However only the short circuit current (Isc) and maximum current (Imax) and fill factor (FF) increased for 5 to 7.5 minutes microwave exposure whereas, open circuit voltage (Voc) and maximum voltage (Vmax) decreased resulting an overall decrease in the performance of the solar cells. Further increase in the microwave exposure time resulted in decrease of performance parameters. This study indicates possible use of microwave radiations in the tuning of properties of the solar cell. Possibly using different solvents and using lower power microwave radiation the overall performance of the solar cell may increase.

This paper presents the potential of natural fibre in brake friction materials. Natural fibre filled ecofriendly brake friction materials were developed without Kevlar fibre evaluated for tribo-performance on a chase friction testing machine following SAE J 661a standard. Experimental results indicated that natural fibre enhances the fade performance, but depresses the friction and wear performance, whereas Kevlar fibre improves the friction, wear and recovery performance but depresses the fade performance. Also the results revealed that with the increase in natural fibre content, the friction and fade performances enhanced.

This paper defines in detail about the diverse fractal patch antenna. Microstrip patch antennas has evolved in the field of research and development extending its impact across wide range of applications. A combination of patch antenna with fractal patterns has become a tryout to outspread it further. Because of its low profile nature patch antennas have added to a lot of prominence. Apart from have this property it can also be renovated further for wide bandwidth (2929 MHz) applications, as it exhibits self-analogous property. This antenna is premeditated on a patch using Sierpinski(4.040 GHz, 6.566 GHz) and Koch fractal geometries respectively. The antenna is designed using HFSS software.This paper defines in detail about the diverse fractal patch antenna. Microstrip patch antennas has evolved in the field of research and development extending its impact across wide range of applications. A combination of patch antenna with fractal patterns has become a tryout to outspread it further. Because of its low profile nature patch antennas have added to a lot of prominence. Apart from have this property it can also be renovated further for wide bandwidth (2929 MHz) applications, as it exhibits self-analogous property. This antenna is premeditated on a patch using Sierpinski(4.040 GHz, 6.566 GHz) and Koch fractal geometries respectively. The antenna is designed using HFSS software.

In nanoscience, hybrid material based on polymer and nanoparticles are of great interest because of much improved properties of components. Polymers are of enormous interest because of their various properties like flexibility, low weight and easy processing. Here, we studied the influence of ZrO2 nanoparticles on the structural and optical properties of Polyaniline (PANI). ZrO2 mixed with PANI, improve its structural and optical properties. XRD studies reveal that ZrO2 nanoparticles exist in the tetragonal phase in ZrO2/PANI nanocomposites. UV-Vis spectroscopic studies have been carried out to understand the presence of various energy levels and their involvement in absorbance of light. In PANI nanocomposites, aniline monomer attach with ZrO2 nanoparticles through p-p stacking interaction, Vander waal force and hydrogen bonding interaction.In nanoscience, hybrid material based on polymer and nanoparticles are of great interest because of much improved properties of components. Polymers are of enormous interest because of their various properties like flexibility, low weight and easy processing. Here, we studied the influence of ZrO2 nanoparticles on the structural and optical properties of Polyaniline (PANI). ZrO2 mixed with PANI, improve its structural and optical properties. XRD studies reveal that ZrO2 nanoparticles exist in the tetragonal phase in ZrO2/PANI nanocomposites. UV-Vis spectroscopic studies have been carried out to understand the presence of various energy levels and their involvement in absorbance of light. In PANI nanocomposites, aniline monomer attach with ZrO2 nanoparticles through p-p stacking interaction, Vander waal force and hydrogen bonding interaction.

In this paper, we investigate the challenges in timing model generation for designs operating at various functional modes and timing corners for reducing the overall complexity of timing verification besides preserving the key intent of IP protection. We also propose a method for concurrently generating a model that can address the requirements of timing verification of a set of functional constraint modes belonging to the same corner with a given process, voltage and temperature specifications. Eventually we present a comparison of this proposed technique to the standard timing model generation technique and outline the advantages in three metrics of accuracy, performance and compaction of the timing models.

Logic depth aware static timing analysis involves a pre-characterized library that models the variability over the path on the basis of total timing path depth. With shrinking design geometries and rush to pack more components in a reduced size chip, hierarchical timing analysis has emerged as a stronger alternative to closing the designs however logic depth based timing analysis brings new set of challenges in generating timing models for the multiply instantiated hierarchical blocks at the chip level. In this paper, we discuss challenges imposed by logic depth in creating hierarchical timing analysis and propose a new algorithm in generating a model comprehending logic depths for multiply instantiated blocks. We demonstrate that usage of such timing model generation algorithm can significantly speedup the process of model extraction and process accuracy within 10% of the original block timing.

Probabilistic or statistical timing analysis involves dealing with the delay and slew sensitivities for device or interconnects for a given parameter. With shrinking design geometries and rush to pack more components in a reduced size chip, challenges involving device location, their correlation come into play. In this paper, we discuss challenges imposed by probabilistic timing analysis specifically on the timing model characterization and take a case study to demonstrate the impact on usage of such models in P&R flow. We demonstrate that usage of such timing models can reduce pessimism up to 10% in the flow compared with standard on-chip-variation analysis.

Graphene is synthesized by microwave irradiation (MWI) of graphene oxide (GO) and subsequent sonication. MWI of GO is carried in a household microwave oven without using any reducing agents. Sonication of microwave irradiated GO is carried out in distilled water using a probe type sonicator. This method does not evolve any unsafe by-product gases which is otherwise the case when reducing agents are used in the reduction of GO to graphene. Moreover, due to its intrinsic nature, the method is scalable and cost effective. The synthesized product has been characterized as graphene using micro Raman scattering, x-ray diffraction and electron diffraction. Diffraction results show that the synthesized graphene is highly oriented.

In this paper, we have made an analysis of the optics of magnetic photonic crystals having mu-negative materials. We consider the magnetic photonic crystal with different values of the magnetic permeability of the materials (PIM). Such materials will be affected by the applied magnetic field and can also exhibit the properties of superconducting materials. We infer that PhC with MNM and PIM materials can be used as tunable devices by choosing proper thickness, damping factor, and mu-value of the PIM.

We have studied the thermal hysteresis of dc electrical resistivity on the stoichiometric Nd0.67Sr0.33MnO3 and Pr0.67Sr0.33MnO3 manganites. The polycrystalline samples have been synthesized by solid state reaction method. The prepared samples were characterized by X-ray diffraction (XRD) for phase formation and low temperature dc resistivity measurement during both cooling and warming with standard four probe technique. The XRD patterns are indexed in orthorhombic unit cell (space group-Pnma). The resistivity data show a metal–insulator phase transition for both Pr0.67Sr0.33MnO3 and Nd0.67Sr0.33MnO3 samples with observable thermal hysteresis. Thermal coefficient of resistivity of all samples has also been studied.

The effect of chemical pressure on the structural and electrical transport properties of a series of compound of type Y1−xDyxBaCo4O7 has been investigated. Rietveld analysis of XRD data was carried out for all the samples. The four probe resistivity measurements were carried out to understand the transport mechanism in these compounds at low temperatures. The average hopping distance has also been calculated.

We investigate a series of compounds of the type, Y1-xYbxBaCo4O7, to study the effect of chemical pressure on the structural and electrical transport properties of a geometrically frustrated cobaltite, YBaCo4O7. Rietveld analysis of XRD data were carried out for all the samples studied. The four probe resistivity measurements were carried out to understand the transport mechanism in these compounds at temperatures below room temperatures. These results are presented and discussed in the context of ongoing efforts in studying geometrically frustrated magnetic compounds with novel physical properties.

Search Engine gives an ordered list of web search results in response to a user query, wherein the important pages are usually displayed at the top with less important ones afterwards. It may be possible that the user may have to look for many screen results to get the required documents. In literatures, many page ranking algorithms has been given to find the page rank of a page. For example PageRank is considered in this work. This algorithm treats all the links equally when distributing rank scores. That's why this algorithm some time gives equal importance to all the pages. But in real this can not be happen because, if two pages have same rank then how we can judge which page is more important then other. So this paper proposes another idea to organize the search results and describe which page is more important when confliction of same rank is produced by the PageRank. So that the user can get more relevant and important results easily and in a short span of time.

To realize direct image of faint object which is in the close proximity of very bright object could be technologically feasible by introducing asymmetric apodization. The point spread function (PSF) of an optical system with asymmetric apodization has been found to possess a so‐called good side and a bad side. The good‐side has decreased side lobes whereas the bad‐side shows increased side lobes. This has been observed when the aperture is divided into three parts viz. two semi‐circular edge rings and a central region with an apodizer. The asymmetry in the PSF has been found to increase with the width of the edge rings and is seen to decrease with the increased apodization of the central region.

Do In this paper presents recent advances in technology have made low‐cost, low‐power wireless sensors with efficient energy consumption. A network of such nodes can coordinate among themselves for distributed sensing and processing of certain data. For which, we propose an architecture to provide a stateless solution in sensor networks for efficient routing in wireless sensor networks. This type of architecture is known as Tree Cast. We propose a unique method of address allocation, building up multiple disjoint trees which are geographically inter‐twined and rooted at the data sink. Using these trees, routing messages to and from the sink node without maintaining any routing state in the sensor nodes is possible. In this paper, we introduce the wormhole attack, a severe attack in ad hoc networks that is particularly challenging to defend against. The wormhole attack is possible even if the attacker has not compromised any hosts and even if all communication provides authenticity and confidentiality. In the wormhole attack, an attacker records packets (or bits) at one location in the network, tunnels them to another location, and retransmits them there into the network. The wormhole attack can form a serious threat in wireless networks, especially against many sensor network routing protocols and location‐based wireless security systems. For example, most existing ad hoc network routing protocols, without some mechanism to defend against the wormhole attack, would be unable to find routes longer than one or two hops, severely disrupting communication. We present a new, general mechanism, called packet leashes, for detecting and thus defending against wormhole attacks, and we present a specific protocol, called TIK, that implements leashes.

In this paper presents recent advances in technology have made low‐cost, low‐power wireless sensors with efficient energy consumption. A network of such nodes can coordinate among themselves for distributed sensing and processing of certain data. For which, we propose an architecture to provide a stateless solution in sensor networks for efficient routing in wireless sensor networks. This type of architecture is known as Tree Cast. We propose a unique method of address allocation, building up multiple disjoint trees which are geographically inter‐twined and rooted at the data sink. Using these trees, routing messages to and from the sink node without maintaining any routing state in the sensor nodes is possible. In contrast to traditional solutions, where the IT services are under proper physical, logical and personnel controls, this routing architecture moves the application software and databases to the large data centers, where the management of the data and services may not be fully trustworthy. This ...