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Fire breakout in buildings is a major threat now days. These accidents cause loss of life and property. To find the reason behind, frequency and giving protection to all type of buildings became challenges to the fire rescue team. There are a lot of problems faced by fire fighters in the event of a fire breakout. Some of these include lack of knowledge about the building construction, fire behavior, communication between firefighters and knowing about the building tenability and victim viability. This work deals with the application of a Quadcopter with an IR camera to overcome the major problems faced during firefighting. The components of our project include fire detection using IR camera and sending the information received by the quad copter to the concerned fire rescue team.

According to the latest report of the World Health Organization, 7 lakh 83 thousand people die due to polluted water every year in India. The main challenge of the Government of India is to provide clean water to the public. Therefore, in the study presented, an attempt has been made to know why there is pollution of drinking water, what types of diseases are caused by this polluted water, d. An attempt has been made to know its negative effects and pure drinking water treatment. The data and facts have been compiled on a secondary basis. विष्व स्वास्थ संगठन की ताजा रिपोर्ट के अनुसार भारत में प्रतिवर्ष 7 लाख 83 हजार लोग प्रदूषित जल की वजह से मरते है। जनता को साफ पानी पहुचाना भारत सरकार की मुख्य चुनौति है। अतः प्रस्तुत अध्ययन में यह जानने का प्रयास किया गया है कि पेयजल प्रदुषण क्यों होता है घ् इस प्रदूषित जल से किस प्रकार की बीमारियाँ उत्पन्न होती है घ् इसके नकारात्मक प्रभाव एवं शुध्द पेयजल उपचार को जानने का प्रयास किया गया है। आंकड़ो व तथ्यों का संकलन द्वितीयक आधार पर किया गया है।

Smart materials, which exhibit piezoelectricity, find an eclectic range of applications in the industry. The direct piezoelectric effect has been widely used in sensor design, and the inverse piezoelectric effect has been applied in actuator design. Ever since 1954, PZT and BaTiO3 were widely used for sensor and actuator applications despite their toxicity, brittleness, inflexibility, etc. With the discovery of PVDF in 1969, followed by development of copolymers, a flexible, easy to process, nontoxic, high density alternate with high piezoelectric voltage coefficient was available. In the past 20 years, heterostructural materials like polymer ceramic composites, have received lot of attention, since these materials combine the excellent pyroelectric and piezoelectric properties of ceramics with the flexibility, processing facility, and strength of the polymers resulting in relatively high dielectric permittivity and breakdown strength, which are not attainable in a single phase piezoelectric material. The current review article is an attempt to provide a compendium of all the work carried out with reference to PVDF-PZT composites. The review article evaluates the effect of grain size, content and other factors under the purview of dielectric and piezoelectric properties while evaluating the sensitivity of the material for sensor application. POLYM. ENG. SCI., 55:1589–1616, 2015. © 2015 Society of Plastics Engineers

Almost every business uses SMS for various reasons to increase sales and brand exposure and Mass alert to everyone. 80% of cell phone users carry their phone all the time. Sending a text message to their cell phones is the perfect way to alert them of any urgent information, such as a change of appointment, or product ready for pickup etc. Mass alert are an ideal way for school districts to send alerts to parents regarding school closings, changes in schedules etc. The short message service (SMS) is one of the highly used and well-tried mobile services with global availability within all GSM/CDMA networks. The existing SMS is limited to the transmission of secure plain text between different mobile phone subscribers and server for different purpose. SMS does not have any built-in procedure to authenticate the text and offer security for the text transmitted as data [5], because most of the applications for mobile devices are designed and developed without taking security into consideration [6] [7], But we can use SMS service to protect our financial transaction by enable or disable the account apply some security on SMS. It will help to control fraud on financial traction by ATM or online fund transfer. In this paper detail an overview of SMS transmission and how to apply security on SMS to transfer from one point to another point.

A Mobile Ad hoc Network (MANET) is an infrastructure-less network of wireless mobile nodes that can communicate with one another directly or via intermediate nodes. Connectivity breaks between nodes, resulting from random fashioned nodes movement, are a serious problem for MANET routing protocols. Though, sometimes the selected routes which are based on hop count are having weak quality links, implies low SNR, which results higher rate of frame error, higher end to end delay and lower throughput. This present mechanism permits the network layer to modify its routing protocol dependent on Received Power and SNR along the source to destination route for every transmission link. This proposed routing method uses signal-to-noise ratio (SNR) of a link for getting value of its sojourn time and allot a link cost value on the basis of calculated sojourn time. Sojourn time is assumed to follow a Rayleigh distribution. Link cost is inversely proportional to sojourn time. Node which is connected to its previous node with less link cost is chosen as next neighbor node on the way of source to destination route establishment. The performance analysis was evaluating our approach (Sojourn Time-ST-AODV) and AODV, to illustrate that our proposed methodology improved the performance of AODV. Finally, justify network performance on NS-2 network simulator platform depending on the basic network parameters such as delay and throughput in respect of nodes and different transmission rates of mobile nodes.

For the emerging digital video broadcast applications of satellite communication system, there is a demand to achieve the low bit error rate, reduced receiver end processing delay with high data rate transmission. Advance forward error correction techniques such as LDPC codes, Turbo codes and BCH codes can be employed to achieve this. LDPC code provides the high throughput, high data rate, improved coding gain and low complexity. It provides a coding gain of 5.12 dB at 3.1×10−3 bit error rate in comparison with convolution code over fading environment however LDPC codes give flat error performance beyond a certain value of SNR, known as error floor region. To improve this, LDPC codes along with BCH code are used for emerging application of satellite communication e. g. digital video broadcast satellite/terrestrial (DVB-S2/T2). Present paper analyzes the performance of forward error correction subsystem (BCH code along with LDPC code) in video broadcast satellite system.

The growing demand for voice and multimedia services on wireless communication spur the advancement of efficient error detection and correction coding techniques. The error correcting capability of any encoding technique depends on the number of parity bits added and position, where the parity bits are placed. Low density parity check code having sparse parity check matrix provides the ability to reach near the Shannon limit over the fading and non-fading channel. In this paper, the impact of LDPC Code on the performance of communication system over various channel are analyzed by considering different modulation scheme, Eb/No value, size of signal constellation and code rate. The value of code rate less than or equal to 2/3, LDPC Code acquires the negligible bit error rate regarding the minimum value of Eb/No (8.5 dB) and maximum value of size of signal constellation (16) with PSK modulation scheme. The obtained results are useful to improve the performance and proper utilization of power and bandwidth in wireless communication application.

The presented work proposes a suitable power converter design for a Wind Energy Conversion System (WECS) connected to a variable speed Permanent Magnet Synchronous Generator (PMSG) for grid integrated operations. In the present work energy is derived from WECS and fed to the PMSG. Due to the non-uniformity of the wind velocities the voltage and frequency gained as output of the generator are variable quantities, so that it cannot be synchronized with the grid. The output of the generator is rectified using an uncontrolled three phase diode-rectifier and a constant value is achieved using a closed loop DC-DC converter. The controlled DC-DC Converter is designed using a PI controller based feedback control. Output voltage is continuously sensed and corresponding change in duty ratio of the switch maintains a constant DC-link voltage. The three-phase voltage source inverter (VSI) receives the output of the controlled converter. The inverter uses pulse width modulation (PWM) technique and its output is fed to a variable load which is connected to a grid. Simulation of proposed scheme is presented by MATLAB-Simulink model and the results demonstrate the validity of the developed model.

Research Summary - Colors have a profound effect on our brain, body and emotions. The imbalance of colors is the cause of disease. If the treatment method of colors removes this imbalance, then a person can become healthy and disease free. In the study presented, an attempt has been made to know what is the color therapy system, whether it can lead to disease diagnosis, whether it is a less expensive method, etc. an attempt has been made to know things. शोध सारांष - रंगों का हमारे मस्तिष्क, शरीर व भावनाओं पर गहरा असर पड़ता हैं। रंगों का असन्तुलन रोग का कारण होता है यदि रंगों की चिकित्सा विधि द्वारा इस असन्तुलन को दूर कर दिया ताय तो व्यक्ति स्वस्थ एवं रोग मुक्त हो सकता हैं। प्रस्तुत अध्ययन में यह जानने का प्रयास किया गया है कि रंग चिकित्सा प्रणाली क्या है घ् क्या इससे रोग निदान हो सकता है घ् क्या यह कम खर्चीली पद्धति है घ् आदि बातों को जानने का प्रयास किया गया है।

Carbon dots are promising scaffolds for multifunctional therapeutic systems because of their fluorescence property, good biocompatibility, and low toxicity. In this work, we prepared nitrogen-doped carbon dots through an aqueous phase strategy using folic acid as precursor. The carbon dots possess many attractive features including uniform dispersion with size about 9 nm, bright photoluminescence, high photoluminescence quantum yield of 23%, and low toxicity, making them excellent imaging probes for biomedical applications.

The effects of γ‐irradiation on the dielectric properties of stretched and poled polyvinylidene fluoride thin films synthesized by solvent cast method are reported. The films are subjected to γ‐irradiation with different doses (25, 50, and 75 kGy). XRD pattern is obtained to identify the presence of α/β phases. Dielectric constant and loss values of the stretched and poled films have been measured, before and after irradiation, and their nature of variation has been studied. β phase is retained even after the irradiation thereby confirming that the radiation damage is not significant. The dielectric loss is minimum in the frequency range 102 to104 Hz, giving the preferable frequency range of operation for devices

Piezoelectric polymer-ceramic composites are promising materials for transducer applications. PVDF-PZT composite films have been developed with different weight fraction and particle size of PZT using a solvent cast method. Films are investigated using X-ray diffraction technique, scanning electron microscopy, Fourier transformed infrared spectroscopy, and differential scanning calorimetry to study crystal structural changes, distribution of particles within the polymer matrix, the influence of these particles at the molecular level, and the changes induced in the melting transition and in the degree of crystallinity of the composites, respectively. The variation in these properties as a function of weight fraction (10–50%) and particle size (1 μm and ∼25 μm) of PZT has also been investigated. The composite films are tested for their application as acoustic emission (AE) sensor.

Internet of Things (IoT) has been a focus of research in the last decade with emphasis on the security aspects like wireless network security, communication security, sensor data security, integrity of physical signals and actuating devices. The existing security techniques are not suitable for IoT applications as the involved devices at the ground level have limited resources, low complexity, energy constraints etc. This survey analyzes various IoT concepts in terms of IoT elements, architecture and communication standards. We also analyze the existing wireless security techniques and security attacks at all the layers of the Open Systems Interconnection (OSI) model with special attention on applicability of wireless physical layer security (WPLS) techniques to achieve security for IoT devices.

Past few decades have proved that the number of vehicles are increasing on road so we need some extra improvisation for our traffic safety need. The rise in vehicles count has led to a requirement for communication between vehicles. The emerging Vehicular ad hoc network (VANET) is a new class of wireless network, which offer intelligent transportation for the people on vehicle. Due to dynamic nature of traffic environment and very high mobility of vehicles, VANETs suffer link breakage problem. So in order to offer stable routes and establish good throughput in VANET, appropriate routing must be required. Many routing protocol are already available for efficient communication in Mobile ad hoc network (MANET) and one of those most important and efficient is Ad hoc on demand Distance Vector Routing (AODV) and it can be further used for communication and routing purpose in VANET environment. Due to different mobility and characteristic of MANET and VANET, AODV protocol does not perform well when we use existing AODV of MANET directly in VANET environment. So this paper presents optimization in route selection and route maintenance to get better stability of route and decrease overhead. Protocol proposed in this paper get improvement over previously proposed AODV protocol in terms of throughput, broken links.

In this article, Power generation system model includes a turbine model of wind system, PMSG model, and a Simulink model of drive train. The generated power through the wind power plant is fed to three phase linear and non-linear load. The power electronics based shunt connected custom power devices are used to suppress the power quality problems at constant speed turbine. The objective of this paper is to compensate harmonic and reactive power due to non-linearity of loads and maintained rated voltage at the point of common interface (PCI). This shunt connected compensator as a DSTATCOM is controlled through variable step learning based adaptive control algorithm. The simulation waveforms show the satisfactory performance of PMSG System and the control algorithm.

Sewing cuffs incorporated within tissue-engineered blood vessels (TEBVs) enable graft anastomosis in vivo, and secure TEBVs to bioreactors in vitro. Alternative approaches to cuff design are required to achieve cuff integration with scaffold-free TEBVs during tissue maturation. To create porous materials that promote tissue integration, we used electrospinning to fabricate cuffs from polycaprolactone (PCL), PCL blended with gelatin, and PCL coated with gelatin, and evaluated cuff mechanical properties, porosity, and cellular attachment and infiltration. Gelatin blending significantly decreased cuff ultimate tensile stress and failure strain over PCL alone, but no significant differences were observed in elastic modulus or failure load. Interestingly, gelatin incorporation by blending or coating did not produce significant differences in cellular attachment or pore size. We then created tissue tubes by fusing self-assembled smooth muscle cell rings together with electrospun cuffs on either end. After 7 days, rings and cuffs fused seamlessly, and the resulting tubes were harvested for pull-to-failure tests to measure the strength of cuff-tissue integration. Tubes with gelatin-coated PCL cuffs failed more frequently at the cuff-tissue interface compared to PCL and PCL:gelatin blended groups. This work demonstrates that electrospun cuffs integrated successfully with scaffold-free TEBVs, and that the addition of gelatin did not significantly improve cuff integration over PCL alone for this application. Electrospun cuffs may aid cannulation for dynamic culture and testing of tubular constructs during engineered tissue maturation. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 817-826, 2018.

Glioblastoma multiforme (GBM) is an aggressive and invasive brain tumor. Current interventional strategies have been minimally successful. Three key characteristics of GBMs are (1) enhanced resistance to apoptosis, (2) increased proliferation rate, and (3) increased invasion potential, making them difficult to treat. MicroRNAs (miRs) have demonstrated beneficial therapeutic intervention; particularly miRs 34a and 21, which have been implicated in regulation of apoptosis, senescence, and invasion of GBM tumor cells. MiR21 is anti-apoptotic and pro-proliferative, whereas miR34a is proapoptotic and an anti-invasive regulator in tumor cells. Our study investigates the effects of modulating both miR34a and miR21, in addition to comparing the two individual treatments. Using targeted cationic liposomes that bind to the epidermal growth factor receptor (EGFR), we delivered miR34a and/or anti-sense oligonucleotide to miR21 (ASO21) to GBM tumor cell lines, U87MG and A172, in vitro. Our data demonstrate that co-delivery of miR34a and ASO21 results in enhanced reduction in viability and invasion, while increasing senescence in vitro. Additionally, there were significant decreases in pro-invasion and -proliferation gene markers, as well as an increase in pro-apoptotic markers. In vivo results demonstrate that the combination of miR34a and ASO21 reduced tumor volume and proliferation of the A172 tumor cells. Accumulation of rhodamine encapsulated EGFR-targeted cationic liposomes was observed throughout the primary tumor bed after systemic injection. To our knowledge, we are the first to modulate multiple miRs, while using a targeted cationic liposomal delivery for miR-based therapy. These results demonstrate a potential clinically relevant, miR therapeutic strategy for GBM.

Glioblastoma multiforme (GBM) is an aggressive, Grade IV astrocytoma with a poor survival rate, primarily due to the GBM tumor cells migrating away from the primary tumor site along the nanotopography of white matter tracts and blood vessels. It is unclear whether this nanotopography influences the biomechanical properties (i.e. cytoskeletal stiffness) of GBM tumor cells. Although GBM tumor cells have an innate propensity to migrate, we believe this capability is enhanced due to the influence of nanotopography on the tumor cells’ biomechanical properties. In this study, we used an aligned nanofiber film that mimics the nanotopography in the tumor microenvironment to investigate the mechanical properties of GBM tumor cells in vitro. The data demonstrate that the cytoskeletal stiffness, cell traction stress, and focal adhesion area were significantly lower in the GBM tumor cells compared to healthy astrocytes. Moreover, the cytoskeletal stiffness was significantly reduced when cultured on aligned nanofiber films compared to smooth and randomly aligned nanofiber films. Gene expression analysis showed that tumor cells cultured on the aligned nanotopography upregulated key migratory genes and downregulated key proliferative genes. Therefore, our data suggest that the migratory potential is elevated when GBM tumor cells are migrating along aligned nanotopographical substrates.

Characterization of a mobile radio channel plays an important role in designing a reliable wireless communication system. Such channels are analyzed by two state model, namely satisfactory and outage state. This paper presents the analysis to estimate fading parameters of wireless channel with omission of certain outage durations which are considered as “Tolerance time”. Minimum outage duration which can be tolerated by a wireless fading channel to achieve desired packet error rate is defined as tolerance time. Normally a system with tolerable minimum outage time is analyzed based on Fade Duration Distribution (FDD) function over Rayleigh channel. In this paper Weibull function is used as FDD for varying tolerance time. The approach is simple and in general applicable from Rayleigh to Nakagami channels. The analysis is extended to study the effect of Tolerance time on channel fading statistics such as Average Fade Duration (AFD) and frequency of outage. Further the effects of various fade margin and Doppler spread on fading parameters are also investigated. The analysis can also be used in case of timeout expiration, connection resetting and congestion window control.

Large-area PVDF thin films have been prepared and characterized for quasi-static and high frequency dynamic strain sensing applications. These films are prepared using hot press method and the piezoelectric phase (beta-phase) has been achieved by thermo-mechanical treatment and poling under DC field. The fabricated films have been characterized for quasi-static strain sensing and the linear strain-voltage relationship obtained is promising. In order to evaluate the ultrasonic sensing properties, a PZT wafer has been used to launch Lamb waves in a metal beam on which the PVDF film sensor is bonded at a distance. The voltage signals obtained from the PVDF films have been compared with another PZT wafer sensor placed on the opposite surface of the beam as a reference signal. Due to higher stiffness and higher thickness of the PZT wafer sensors, certain resonance patterns significantly degrade the sensor sensitivity curves. Whereas, the present results show that the large-area PVDF sensors can be superior with the signal amplitude comparable to that of PZT sensors and with no resonance-induced effect, which is due to low mechanical impedance, smaller thickness and larger area of the PVDF film. Moreover, the developed PVDF sensors are able to capture both A(0) and S-0 modes of Lamb wave, whereas the PZT sensors captures only A(0) mode in the same scale of voltage output. This shows promises in using large-area PVDF films with various surface patterns on structures for distributed sensing and structural health monitoring under quasi-static, vibration and ultrasonic situations. (C) 2010 Elsevier B.V. All rights reserved.

Dynamic Voltage Restorer (DVR) is able to protect critical loads against source voltage power quality problems in effectively nature. In this paper, in phase control and minimal energy control technique has been discussed under balanced, unbalanced and distorted non-ideal ac mains. The algorithm based on composite observer has been proposed for both techniques. The three wire distribution system is simulated using MATLAB environments. The performance results are obtained under various supply voltage disturbances. After study, recorded observations are found satisfactory according to IEEE guidelines.

Ni–Co composites incorporated with SiC particles of nano and micron size were produced by electrodeposition. The effect of cobalt content on the particle incorporation, microhardness, surface morphology and tribological behaviour has been studied. The Ni rich Ni–Co composite exhibited enhanced microhardness values. However, no appreciable increase in the microhardness was observed for Co rich Ni–Co–SiC composites. Scanning electron microscope, energy dispersive X-ray analysis and X-ray diffraction studies were used to characterize the coatings. A change in surface morphology, phase structure and SiC incorporation was observed with increase in cobalt content. Pin-on-disc tribo tester was employed to study the wear and friction behaviour of the Ni–Co–SiC coatings. The tribo studies indicated that the wear volume loss was less for micron SiC reinforced Ni–Co composites compared to nano SiC reinforced composites. However, no appreciable variation in the coefficient of friction was observed for both Ni rich and Co rich Ni–Co–SiC composites.

Autocatalytic ternary Ni-Sn-P, Ni-W-P and quaternary Ni-W-Sn-P films were prepared using alkaline citrate-based baths and compared with binary Ni-P coatings. Energy dispersive analysis of X-ray (EDAX) showed that binary Ni-P deposit contained 11.3 wt.% of phosphorus. Codeposition of tungsten in Ni-P matrix resulted in ternary Ni-W-P with 5 wt.% P and 7.8 wt.% of tungsten. Incorporation of tin led to ternary Ni-Sn-P deposit containing 0.4 wt.% Sn and 10.3 wt.% P. Presence of both sodium tungstate and sodium stannate in the basic bath had resulted in quaternary coating with 6.9 wt.% W, traces of Sn and 6.4 wt.% P. X-ray diffraction patterns of all the deposits revealed a single, broad peak which showed the nanocrystalline nature of the deposits. For the first time in related literature, the presence of a metastable phase Ni12P5 in ternary deposits is reported in the present study. Metallographic cross-sections of all the deposits revealed the banded/lamellar structure. Scanning electron microscopy (SEM) studies of the deposits showed smooth nodules for ternary deposits, but coarse and well-defined nodules for quaternary deposits. DSC studies of phase transformation behavior of the ternary Ni-Sn-P deposit revealed a single sharp exothermic peak at 365 xB0;C. However, ternary Ni-W-P and quaternary Ni-W-Sn-P deposits exhibited a low temperature peak at 300 xB0;C, a split type high temperature peak at 405 and 440 xB0;C and a very high temperature peak at 550 xB0; C. Higher activation energy values were obtained for W-based alloy deposits. Presence of W and Sn has helped to retain high microhardness values even at higher temperatures indicating an improved thermal stability.

Single-phase CrN and CrAlN coatings were deposited on silicon and mild steel substrates using a reactive DC magnetron sputtering system. The structural characterization of the coatings was done using X-ray diffraction (XRD). The XRD data showed that both the CrN and CrAlN coatings exhibited B1 NaCl structure with a prominent reflection along (200) plane. The bonding structure of the coatings was characterized by X-ray photoelectron spectroscopy and the surface morphology of the coatings was studied using atomic force microscopy. Subsequently, nanolayered CrN/CrAlN multilayer coatings with a total thickness of approximately 1 m were deposited on silicon substrates at different modulation wavelengths (). The XRD data showed that all the multilayer coatings were textured along {200}. The CrN/CrAlN multilayer coatings exhibited a maximum nanoindentation hardness of 3125 kg/mm2 at a modulation wavelength of 72 A, whereas single layer CrN and CrAlN deposited under similar conditions exhibited hardness values of 2375 and 2800 kg/mm2, respectively. Structural changes as a result of heating of the multilayer coatings in air (400-800C) were characterized using XRD and micro-Raman spectroscopy. The XRD data showed that the multilayer coatings were stable up to a temperature of 650C and peaks pertaining to Cr2O3 started appearing at 700C. These results were confirmed by micro-Raman spectroscopy. Nanoindentation measurements performed on the heat-treated coatings revealed that the multilayer coatings retained hardness as high as 2250 kg/mm2 after annealing up to a temperature of 600°C.

The residual effects of cumulative thermal aging on the crystal structural characteristics of the fluoro carbon poly(tetra fluoro ethylene) (PTFE) have been studied by X-ray diffraction methods. The initial hexagonal arrangement of the PTFE chains in a 157 helical conformation is left unaffected by the exposures to temperatures (T), up to and beyond its melting point, Tm. The unit cell registers a residual anisotropic volume expansion. The anisotropy arises from the enhanced enlargement of the basal plane dimension a compared with the axial dimension c. Conformational changes contributing to the observed increase in the chain length have been examined. Enhancement of residual crystallinity of samples aged at T's lt; Tm suggests that the selective thermal aging could be used as an effective tool to improve the initial crystallinity of commercially available PTFE. The activation energy for 50% enhancement in initial crystallinity has been estimated as 53.9 kJ mol-1. Aging at 400xB0;C, a temperature above Tm, is accompanied by markedly different features viz., deterioration in crystallinity and other structural characteristics. The overall behavior of thermally aged PTFE bears a marked similarity to many polyamides. POLYM. ENG. SCI., 47:1724-1729, 2007. xA9; 2007 Society of Plastics Engineers

Spectrum scarcity is increasing with the growing demand of number of wireless technologies and services. Cognitive Radio (CR) techniques have become reliable solution for solving spectral congestion problem. For utilization of unused electromagnetic spectrum in a cognitive radio network, it is necessary for secondary users to monitor the available spectrum (allocated to primary users) and identify the free spectrum (spectrum holes). In this paper primary user signal and channel noise conditions are discussed. Earlier literature has worked on one of these conditions. What are these conditions? Primary user signal and channel noise can be real valued signal or complex valued signal. There modulation schemes may also be different. In this paper classification of primary user signal and channel noise is discussed. The probability of false alarm, probability of detection and throughput of secondary network (user) is calculated and a comparison of throughput of secondary user for different conditions of primary user signal and channel noise is being presented.

Modern error correcting codes are used in 4G and are proposed for future wireless cellular networks for achieving improved channel error correcting capability. Turbo codes, and their improved variants with better error correcting capabilities, and LDPC codes are near Shannon limit channel codes and are used in such systems. This paper focuses on error correcting codes used in present and future generations of mobile communication systems for improving system performance. These systems have higher data rates and low energy per bit. The comparative performance evaluation of Turbo codes and LDPC codes and their suitability for future cellular network is explored in the paper. This comparison will be useful in the selection of error correcting codes for future mobile communication systems.

The two-way relaying scheme is a network coding scheme which provides efficient utilization of spectrum. The performance of a two-way relaying scheme based on analog network coding (ANC) can be evaluated in context of many parameters such as overall symbol error rate (OSER), overall outage probability (OOP) and ergodic sum rate (ESR). In this paper we analyse the OSER over Nakagami-m fading channels for analog network coding scheme. The variation of OSER with respect to signal to noise ratio (SNR) has been observed for various factors such as fading parameter, modulation scheme used and number of antennas at the source and destination terminal. The threshold range of SNR for a tolerable value of OSER of 0.001 is computed as 20 to 25 dB. The results demonstrate the necessity of high SNR in two way relaying scheme for tolerable OSER. Further the analysis may be useful for selection of various physical layer parameters in design of communication networks.

Proposed is a control strategy of voltage and frequency control for a doubly fed induction generator (DFIG) connected to variable speed wind turbines. The scheme is based on stator voltage vector represented in a rotating polar coordinate system. Modified direct voltage control strategy for rotor side converter is used. The control pulses for the rotor side converter are supplied by the hysteresis controller. Simulation and analysis of a 5HP grid connected variable speed DFIG based on wind power generation system is presented to demonstrate the system performance in different operating conditions. The operating conditions are based on the change in wind velocity.

The X-ray diffraction patterns are recorded from polycrystalline iron sample compressed in a diamond anvil cell up to 55 GPa. The maximum micro-stress in the sample, a measure of compressive strength, is derived from the line-width analysis. The strength of iron in the body centered cubic (BCC)-phase is 1.1amp;plusmn;0.2 GPa. This value is in good agreement with the strength derived from the hardness vs. grain-size data. The strength increases steeply during the BCC-hexagonal closed packed (HCP) transition. The strength-pressure data for HCP-iron fit the relation amp;sigma; = 2.9 + 0.028 P, where amp;sigma; and P are the compressive strength and pressure in GPa, respectively. The present results agree well with those obtained from the line shift analysis carried out in earlier studies.

We have determined the crystallite size of Twaron fibers heat treated at various temperatures by analyzing the wide angle X-ray scattering (WAXS) data employing a profile analysis technique developed by us. This study indicates that the differential change of size with temperature is less than 1% of the mean value along both (110) and (200) directions. Hence, these fibers are thermally stable and thermal aging is negligible. We have also observed that the lattice strain variation with temperature is negligible. These studies demonstrate the thermal stability of fibers in terms of the changes in the microcrystalline parameters. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4910–2916, 2006

TiAlN films were deposited on silicon (1 1 1) substrates from a TiAl target using a reactive DC magnetron sputtering process in Ar+N 2 plasma. Films were prepared at various nitrogen flow rates and TiAl target compositions. Similarly, CrN films were prepared from the reactive sputtering of Cr target. Subsequently, nanolayered TiAlN/CrN multilayer films were deposited at various modulation wavelengths ( Λ ). X-ray diffraction (XRD), energy dispersive X-ray analysis, nanoindentation and atomic force microscopy were used to characterize the films. The XRD confirmed the formation of superlattice structure at low modulation wavelengths. The maximum hardness of TiAlN/CrN multilayers was 3900 kg/mm 2 , whereas TiAlN and CrN films exhibited maximum hardnesses of 3850 and 1000 kg/mm 2 , respectively. Thermal stability of TiAlN and TiAlN/CrN multilayer films was studied by heating the films in air in the temperature range ( T A ) of 500–900 °C for 30 min. The XRD spectra revealed that TiAlN/CrN multilayers were stable up to 800 °C and got oxidized substantially at 900 °C. On the other hand, the TiAlN films were stable up to 700 °C and got completely oxidized at 800 °C. Nanoindentation measurements performed on the films after heat treatment showed that TiAlN retained a hardness of 2200 kg/mm 2 at T A =700 °C and TiAlN/CrN multilayers retained hardness as high as 2600 kg/mm 2 upon annealing at 800° C.

Orthogonal frequency division multiplexing (OFDM) is a technology for high data rate broadband wireless communication system. It provides high spectral efficiency. The main limitation which degrades the performance of OFDM is inter-carrier interference (ICI), which is caused by Doppler frequency offset and transceiver local oscillator frequency offset. To mitigate ICI effect, a new method of ICI reduction using quadrature Kalman filter (QKF) is proposed and investigated. In this paper, we compared proposed method with pulse shaping and self-cancellation methods of ICI reduction for different digital modulation scheme. For simulation purpose AWGN channel is considered and results show that the proposed method outperforms the existing ICI reduction methods.

The occurrence of space group forbidden reflections in the X-ray diffraction patterns from the aramid PPTA has been correlated with the presence of stacking faults. The fraction of sample affected by the presence of such faults has also been estimated.

Nanolayered TiN/CrN multilayer coatings were deposited on silicon substrates using a reactive DC magnetron sputtering process at various modulation wavelengths (?), substrate biases (VB) and substrate temperatures (TS). X-ray diffraction (XRD), nanoindentation and atomic force microscopy (AFM) were used to characterize the coatings. The XRD confirmed the formation of superlattice structure at low modulation wavelengths. The maximum hardness of the TiN/CrN multilayers was 3800kg/mm2 at ?=80 A?, VB=-150V and T S=400xB0;C. Thermal stability of TiN, CrN and TiN/CrN multilayer coatings was studied by heating the coatings in air in the temperature range (TA) of 400-800xB0;C. The XRD data revealed that TiN/CrN multilayers retained superlattice structure even up to 700xB0;C and oxides were detected only after TAamp;gt;750xB0;C, whereas for single layer TiN and CrN coatings oxides were detected even at 550xB0;C and 600xB0;C, respectively. Nanoindentation measurements showed that TiN/CrN multilayers retained a hardness of 2800kg/mm2 upon annealing at 700xB0;C, and this decrease in the hardness was attributed to interdiffusion at the interfaces. xA9; 2003 Elsevier Ltd. All rights reserved.

The residual effects of thermal aging on Twaron fibers have been studied using X-ray diffraction, weight analysis, scanning electron microscopy and tensile testing. X-ray data from isothermally aged fibers indicate the introduction of changes at the level of the crystal lattice, which include reduction in crystallinity, variations in 20 values, half width and azimuthal spread of reflections. Isothermal aging also introduces weight loss. Examination of the surface of fibers has shown that damages in the form of holes, materials deposits, etc., are introduced by isothermal aging. These data on Twaron further show that the thermally induced effects are controlled by two parameters: temperature T and cumulative exposure time to T, i.e. tcum(T). Among the tensile properties, the tensile strength is found to be more sensitive to thermal aging than modulus. In addition to the structural studies on the thermal aging behavior of Twaron, a one-to-one comparison has also been attempted between the tensile behavior of Twaron and Kevlar 49 fibers, which are also made up of the same polymer.

In this research, electromagnetic waves absorbing multilayer composite structures have been developed for terahertz (THz) region. In the recent past, most of the efforts to absorb the THz radiations are based on metamaterials or multilayer coatings, which are narrowband and fragile in nature, respectively. Under this work, we have designed and developed multilayer composite structures for THz absorption. Magnetic materials based composite structure shows more than 99% absorption in 0.5–2 THz frequency region for both TE and TM polarizations. Mechanically stable composite structures with such broadband THz absorptivity have huge potential in aero sector for stealth applications. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:393–395, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27295

Thermally aged Nomex fibres manifest several residual effects viz. reduction in X-ray crystallinity, weight loss and deterioration in tensile characteristics. Surface damages in the form of longitudinal openings, holes, material deposits etc have also been observed. Based on the data from thermally exposed fibres, the time needed for states of zero tensile strength and modulus have been predicted.

The residual effects of thermal ageing at various temperatures on fibres of the aliphatic polyamide Nylon 6,6 have been studied. Both crystal and macro structural characteristics manifest the residual effects. The former category includes changes in intensity, 2θ values and half width. The macro changes include introduction of surface damages in the form of holes, material deposits etc. The fibre also undergoes reduction in weight. The structural changes suggest deterioration in the initial tensile characteristics which has been verified experimentally. A direct correlation between the tensile strength and the angular separation of the equatorial reflections has also been observed.

Higher order fading statistics for continuous process has been modeled and explored for various existing channels such as Rayleigh, Ricean and Nakagami-m, to a great extent. The inherent randomness in wireless channels is one of emerging and open research topic, and as this randomness is highly correlated therefore discrete model have been proposed earlier. In this paper, an alternative formulation of higher order statistics such as level crossing rate and average fade duration in terms of cumulative distribution function and its bivariate function is presented for discrete Weibull fading channel sampled at a certain sampling interval, and is expressed in terms of Marcum-Q function. To reliably characterize the fading severity, close-form expressions for the LCR and AFD are given along with numerical examples to illustrate the exactness of proposed expressions.

The response of Nomex sheets to some penetrants has been analyzed. The process of moisture uptake depends on the relative humidity (RH) of the ambient atmosphere and the initial characteristics of the polymer. In the case of common laboratory solvents,the uptake by the polymer shows an inverse dependence on the molar volume of the former. Although the calendered and the uncalendered Nomex sheets exhibit an overall similarity in their response to various penetrants,quantitative comparison reveals distinct differences.

The field of diagnostics has greatly improved due to the use of polymeric material, thus increasing the ability to understand the pathology of multiple diseases and injuries. This includes the improvement of diagnosing injuries and disease states within the central nervous system (CNS). With many sports- and military-related injuries and progression of an aging population, neurological disorders and neoplasms are becoming increasingly prevalent in society. Researchers are incorporating polymeric biomaterials for use in enhancing traditional diagnostic systems like magnetic resonance imaging, computed tomography, ultrasound, and biosensor devices. This chapter addresses the critical considerations required for an effective CNS diagnostic modality, along with multiple examples of current state-of-the-art research in the field of CNS medical diagnostics.

OFDM is promising technology and has approved for various wireless system like 4G mobile system, Wireless Local Area Network (WLAN), Wimax etc. But due to carrier frequency offset (CFO) causes from Doppler spread and drift in local oscillator frequencies of transceiver leads to inter carrier interference (ICI). The ICI is the biggest limitation of OFDM system. In this paper, an optimized sinc power pulse (OSPP) for mitigation of ICI from OFDM system is proposed. The proposed method is compared with existing sinc power pulse (SPP) method in terms of carrier to interference ratio (CIR) and bit error rate (BER) in additive white Gaussian noise (AWGN) channel and results show that proposed method is better.

Glioblastoma multiforme is an aggressive, invasive brain tumour with a poor survival rate. Available treatments are ineffective and some tumours remain inoperable because of their size or location. The tumours are known to invade and migrate along white matter tracts and blood vessels. Here, we exploit this characteristic of glioblastoma multiforme by engineering aligned polycaprolactone (PCL)-based nanofibres for tumour cells to invade and, hence, guide cells away from the primary tumour site to an extracortical location. This extracortial sink is a cyclopamine drug-conjugated, collagen-based hydrogel. When aligned PCL-nanofibre films in a PCL/polyurethane carrier conduit were inserted in the vicinity of an intracortical human U87MG glioblastoma xenograft, a significant number of human glioblastoma cells migrated along the aligned nanofibre films and underwent apoptosis in the extracortical hydrogel. Tumour volume in the brain was significantly lower following insertion of aligned nanofibre implants compared with the application of smooth fibres or no implants.

The Performance of the Orthogonal Frequency Division Multiplexing (OFDM) is degrade due to Doppler frequency or frequency drift between transmitter and receiver oscillator which causes frequency offset and leads to Inter-Carrier-Interference (ICI). In this paper, we present a new scheme of self-cancellation for ICI mitigation in OFDM system and compared with the existing methods of self-cancellation in terms of carrier-to-interference ratio (CIR) and bit-error rate (BER). The simulation result shows that the proposed scheme outperforms the existing methods.

In the present work, the ultrasonic strain sensing performance of the large area PVDF thin film subjected to the thermal fatigue is studied. The PVDF thin film is prepared using hot press and the piezoelectric phase (beta-phase) has been achieved by thermo-mechanical treatment and poling under DC field. The sensors used in aircrafts for structural health monitoring applications are likely to be subjected to a wide range of temperature fluctuations which may create thermal fatigue in both aircraft structures and in the sensors. Thus, the sensitivity of the PVDF sensors for thermal fatigue needs to be studied for its effective implementation in the structural health monitoring applications. In present work, the fabricated films have been subjected to certain number of thermal cycles which serve as thermal fatigue and are further tested for ultrasonic strain sensitivity at various different frequencies. The PVDF sensor is bonded on the beam specimen at one end and the ultrasonic guided waves are launched with a piezoelectric wafer bonded on another end of the beam. Sensitivity of PVDF sensor in terms of voltage is obtained for increasing number of thermal cycles. Sensitivity variation is studied at various different extent of thermal fatigue. The variation of the sensor sensitivity with frequency due to thermal fatigue at different temperatures is also investigated. The present investigation shows an appropriate temperature range for the application of the PVDF sensors in structural health monitoring.

The I²-phase of polyvinylidene fluoride (PVDF) is well known for its piezoelectric properties. PVDF films have been developed using solvent cast method. The films thus produced are in I±-phase. The I±-phase is transformed to piezoelectric I²-phase when the film is hot-stretched with various different stretching factors at various different temperatures. The films are then characterized in terms of their mechanical properties and surface morphological changes during the transformation from I±- to I²-phases by using X-ray diffraction, differential scanning calorimeter, Raman spectra, Infrared spectra, tensile testing, and scanning electron microscopy. The films showed increased crystallinity with stretching at temperature up to 80°C. The optimum conditions to achieve I²-phase have been discussed in detail. The fabricated PVDF sensors have been tested for free vibration and impact on plate structure, and its response is compared with conventional piezoelectric wafer type sensor. The resonant and antiresonant peaks in the frequency response of PVDF sensor match well with that of lead zirconate titanate wafer sensors. Effective piezoelectric properties and the variations in the frequency response spectra due to free vibration and impact loading conditions are reported. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers.