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This report is on studies directed at the nature of magneto-electric (ME) coupling by ferromagnetic resonance (FMR) under an electric field in a coaxial nanofiber of nickel ferrite (NFO) and lead zirconate titanate (PZT). Fibers with ferrite cores and PZT shells were prepared by electrospinning. The core–shell structure of annealed fibers was confirmed by electron- and scanning probe microscopy. For studies on converse ME effects, i.e., the magnetic response of the fibers to an applied electric field, FMR measurements were done on a single fiber with a near-field scanning microwave microscope (NSMM) at 5–10 GHz by obtaining profiles of both amplitude and phase of the complex scattering parameter S11 as a function of bias magnetic field. The strength of the voltage-ME coupling Av was determined from the shift in the resonance field Hr for bias voltage of V = 0–7 V applied to the fiber. The coefficient Av for the NFO core/PZT shell structure was estimated to be − 1.92 kA/Vm (− 24 Oe/V). A model was developed for the converse ME effects in the fibers and the theoretical estimates are in good agreement with the data.

Development of lead-free BaTiO3/NiFe2O4/BaTiO3 (BTO/NFO/BTO) trilayer structure thin films is significant for the realization of eco-friendly and implantable microelectromechanical systems (MEMS)-based devices. In the present work, we report BTO/NFO/BTO trilayer structure as a representative ferroelectric/ferromagnetic/ferroelectric (FE/FM/FE) system deposited on Pt(111)/TiO2/SiO2/Si using Pulsed Laser Deposition (PLD) technique. We report the ferroelectric, magnetic, and ME properties of BTO/NFO/BTO trilayer nanoscale heterostructure having dimensions 140/80/140 nm, at room temperature. High room temperature dielectric constant ~2145 at 100 Hz with low dielectric loss ~0.05 at 1 MHz is observed. Further, the deposited (BTO/NFO/BTO) tri-layered thin films showed magnetoelectric, multiferroic behavior with remanent polarization of 8.63 μCcm−2 at about 0.25 MV/cm and a reasonably high saturation magnetization of ~16 emu/cm3 at ~10 kOe is witnessed at room temperature. Tri-layered films have shown interesting magnetoelectric (ME) coupling coefficient (αE) ~54.5 mV/cm Oe at room temperature. Published version

SRAM cell stability is the primary concern for future technologies due to process variations like threshold voltage and supply voltage scaling etc. The increased effect of process variation and increase in parasitic resistance and capacitance in Nano scale technologies, the lower supply voltages, continuous increase in the size of SRAMs requires additional techniques such as write assist and read assist to improve the write-ability, readability and stability of SRAM memories. In this paper various write and read assist techniques are analyzed with their pros and cons and each technique is explained with their implementation and their impact on write-ability, readability and stability of the SRAM memory. The SRAM bit cell write-ability is very critical at lower voltages. The impact of the write assist technique analyzed across the process, voltage and temperature range. Along with improving the write-ability of the SRAM cell the write assist techniques will impact the performance, power and area of the chip. At lower voltages the noise margin is very crucial for the SRAM cell stability. Read assist techniques help in improving the cell stability and these techniques analyzed across the process, voltage and temperature range. These read assist techniques not only helps the readability and stability of SRAM bit cells but they also will impact the performance, power and area of the chip.

Ferromagnetic/Ferroelectric/Ferromagnetic (Ni/PZT/Ni) tri-layer artificial multiferroelectric structures in spin capacitor configuration were fabricated by sputtering ferromagnetic electrodes on PZT. Magnetocapacitance, magnetoimpedance, and phase angle measurements were carried out by a wide range of frequencies and magnetic fields at room temperature. We also compared the magnetodielectric measurements with Ni/PZT/Ag and Ag/PZT/Ag tri-layers structures. Ni/PZT/Ni spin capacitor shows a significantly different behavior compared to conventional PZT capacitor with Ag electrode and mixed electrode capacitor with one ferromagnetic and one conventional electrode.

The interactions between electric and magnetic subsystems in a ferroelectric-ferromagnetic composite occur through mechanical forces. Here we discuss results of a systematic investigation on the strength of the magnetic response of the composite to an applied electric field, known as the converse magnetoelectric (CME) effect, and its dependence on the ferroic order parameters and volume fraction for the two phases. Studies were carried out on composites of lead zirconate titanate and 2-30-mu m-thick nickel zinc ferrite (NZFO) films grown by liquid phase epitaxy on lattice matched (100) and (111) MgO substrates. Ferromagnetic resonance was utilized to determine the strength of CME from data on electric field E induced shift in the resonance frequency and its dependence on ferrite film orientation and thickness as well as MgO substrate thickness. The CME coupling coefficient A was found to be a factor of 2 to 4 higher in samples with NZFO films with (100) orientation than for (111) films. A decrease in A was measured with increasing ferrite film thickness and a very significant enhancement in the strength of CME was measured for decreasing MgO thickness. A model for CME that takes into consideration the influence of nonferroic MgO substrate was developed, and estimated A values are in very good agreement with the data. The results presented here are also of importance for a new class of electric field tunable ferrite microwave devices. Public domain – authored by a U.S. government employee

We report exchange bias in (Mn,Zn,Fe) 3 O 4 thin films that are compositionally homogeneous. We show that exchange bias in these Mn–Zn ferrite (MZFO) films can be tuned quite easily through annealing of the as-deposited films. The annealing process increases the crystallinity, as measured by X-ray diffraction (XRD). This improvement in crystallinity is accompanied by lower coercive fields, lower exchange bias fields, and higher saturation magnetizations. Exchange bias in these nominally homogeneous ferrite films is correlated with the degree of both structural and magnetic disorder. Based on the annealing experiments, we believe that these MZFO films may consist of crystalline regions that are separated from one another by disordered regions of the same nominal composition. The disordered regions serve to exchange bias the more structurally and magnetically ordered crystalline MZFO grains, leading to a shift of the magnetic hysteresis loop. Together these results indicate that the magnitude of the exchange bias can be controlled by tuning the degree of crystallinity in the system.

In the field of data mining, clustering is one of the major issues. In the categorical clustering, data labeling has been acknowledged as an important method. The grouping of all the similar data points together is called as clustering. Those points which are not labeled earlier go through the data labeling process. For categorical data, very limited algorithms are applied, although there are many approaches in the numerical domain. In categorical domain, the most challenging issue is to allocate all the unlabeled data points into proper clusters. In this paper, a method is anticipated for labeling and maintaining the similar data points into proper clusters. We have a data set named US Census, where the data was collected as part of the 1990 census. There are 68 categorical attributes. This data set was derived from the US Census 1990 raw data set. The new proposal is to allocate each unlabeled data point into the equivalent proper cluster with data labeling also. It is much useful to understand the demographic survey of the public. This method has two rewards: (1) The proposed algorithm exhibits high execution efficiency. (2) This algorithm can achieve superiority clusters. The proposed algorithm is empirically validated on US Census data set, and it is shown considerably more efficient than previous works while attaining results of high quality.

Ferrite-ferroelectric core-shell nanoparticles were prepared by deoxyribonucleic acid (DNA) assisted self-assembly and the strained mediated magneto-electric (ME) interactions between the ferroic phases were studied. The nanoparticle type and size were varied and the DNA linker sequence was also varied. Two kinds of particles, one with 600 nm barium titanate (BTO) core and 200 nm nickel ferrite (NFO) shell and another with 200 nm BTO core and 50 nm nickel cobalt ferrite (NCFO) shell were prepared. The particles were linked by three different oligomeric DNA containing 19, 18 or 30 base pairs. The core-shell structure was evident from electron microscopy and scanning microwave microscopy images. Films and disks of the core-shell particles were assembled in a magnetic field and used for measurements of low frequency ME voltage coefficient (MEVC) and magnet-dielectric effect. The MEVC data on films indicate that particles assembled with DNA with 30 base pairs exhibit the strongest ME coupling suggesting a more fully integrated heterogenous nanocomposite and the weakest interaction for DNA with 18 base pairs. These results indicate that the longer linker region in DNA is the key factor for forming better composites. This result may be due to the irregular shape of the nanoparticles. Longer DNA strands would be able to bridge better generating more linkages. Shorter strands would not able to bridge the irregularly shaped particles as well and therefore result in linkages and less heterogeneity in the composites.

Ferromagnetic–ferroelectric nanocomposites are of interest for realizing strong strain-mediated coupling between electric and magnetic subsystems due to a high surface area-to-volume ratio. This report is on the synthesis of nickel ferrite (NFO)–barium titanate (BTO) core–shell nanofibers, magnetic field assisted assembly into superstructures, and studies on magneto-electric (ME) interactions. Electrospinning techniques were used to prepare coaxial fibers of 0.5–1.5 micron in diameter. The core–shell structure of annealed fibers was confirmed by electron microscopy and scanning probe microscopy. The fibers were assembled into discs and films in a uniform magnetic field or in a field gradient. Studies on ME coupling in the assembled films and discs were done by magnetic field (H)-induced polarization, magneto–dielectric effects at low frequencies and at 16–24 GHz, and low-frequency ME voltage coefficients (MEVC). We measured ~2–7% change in remnant polarization and in the permittivity for H = 7 kOe, and a MEVC of 0.4 mV/cm Oe at 30 Hz. A model has been developed for low-frequency ME effects in an assembly of fibers and takes into account dipole–dipole interactions between the fibers and fiber discontinuity. Theoretical estimates for the low-frequency MEVC have been compared with the data. These results indicate strong ME coupling in superstructures of the core–shell fibers.

Ferromagnetic-ferroelectric composites have attracted interests in recent years for use as magnetic field sensors. The sensing is based on magneto-electric (ME) coupling between the electric and magnetic subsystems and is mediated by mechanical strain. Such sensors for AC magnetic fields require a bias magnetic field to achieve pT-sensitivity. Here we discuss measurements and theory for a novel passive, AC magnetic sensor that does not require a bias magnetic field and is based on a PZT bimorph with a permanent magnet proof mass. Mechanical strain on the PZT bimorph in this case is produced by interaction between the applied AC magnetic field and remnant magnetization of the permanent magnet, resulting in an induced voltage across PZT. Our studies have been performed on sensors with a bimorph of oppositely poled PZT platelets and a NdFeB permanent magnet proof mass. Magnetic floor noise N on the order of 100 pT per sqrHz and 10 nT per sqrHz are measured at 1 Hz and 10 Hz, respectively. When the AC magnetic field is applied at the bending resonance of 40 Hz for the bimorph, the measured N 700 pT per sqrHz. We also discuss a theory for the magneto-electro-mechanical coupling at low frequency and bending resonance in the sensor and theoretical estimates of ME voltage coefficients are in very good agreement with the data.

Satellite image information Enhancement is very important for computer vision and analysis of the data. The satellite image information losses with lack of actualization sensors and different types of noise added at processing stages. Some standard traditional methods and non windowing techniques gave unsatisfactory results, here we proposed new algorithm for advanced morphological techniques with combination of windowing methods for improving Edge enhancement and detection. Obtained satisfactory results and good performance of PSNR and RMSE values. In this proposed method Structuring element (SE) impact on Morphological operations and it introduce with help of Set Theory.

Theory and results of a systematic study on the nature of nonlinear magnetoelectric (ME) interactions in layered ferromagnetic and ferroelectric composites are discussed. The model that considers the nonlinearity associated with magnetostriction of the ferromagnet is to result in (i) a dc component and (ii) frequency doubling when the composite is subjected to an ac magnetic field. In the presence of two ac magnetic fields of different frequencies, nonlinear effects give rise to generation of ME voltages at the sum and difference of the fields frequencies. The efficiencies of nonlinear ME interactions are shown to be a function of the second derivative of the magnetostriction with respect to the bias magnetic field. The predictions of the model are compared with data for bilayers of lead zirconate titanate (PZT) and ferromagnetic layers with wide variations in saturation magnetostrictions and saturation magnetic fields, i.e., an amorphous ferromagnetic (AF) alloy, Ni, or permendur. Under linear excitation conditions an enhancement in the ME voltage is measured when the ac magnetic field is applied at the acoustic mode frequencies. Under nonlinear excitation conditions the mechanical deformation and the ME response occur at twice the excitation frequency and the AF-PZT composite shows a much higher nonlinear ME effects. In addition, the AF-PZT shows an efficient frequency mixing than the samples with Ni or permendur when subjected to two ac magnetic fields. The frequency mixing is shown to be of importance for magnetic field sensor applications.

The nature of mechanical strain mediated electromagnetic coupling in multiferroic composites has been studied extensively in recent years. This review is on composites with ferromagnetic or ferrimagnetic oxides and ferroelectrics. Systems studied so far include samples with spinel ferrites, hexagonal ferrites or lanthanum manganites for the ferromagnetic phase and barium titanate, lead zirconate titanate (PZT), lead magnesium niobate–lead titanate (PMN-PT) or lead zinc niobate–lead titanate (PZN-PT) for the ferroelectric phase. Bilayer and multilayer heterostructures, bulk composites, core shell nanoparticles and core shell nanotubes and nanowires were investigated for their response to magnetic fields, termed direct magnetoelectric effect (DME). Several systems show a giant low frequency DME and resonance enhancement at bending and electromechanical resonance. The response of the composites to an electric field, called converse ME effect, is found to be strong in several ferrite–ferroelectric com...

There have been considerable interests in recent years in ferrite-ferroelectric composites for dual magneticand electric field tunable microwave and mm-wave devices such as resonators, filters, and phase shifters. Low-loss spinel and hexagonal ferrites are used in high frequency devices and the tuning in general is with a magnetic field H. When the ferrite is replaced by a ferrite-ferroelectric composite, however, the piezoelectric strain due to an electric field E applied to the ferroelectric will manifest as an induced anisotropy in the ferrite and facilitate E-tuning of the device. This review focuses on recent efforts on voltage tunable ferrite filters. A related phenomenon of importance is the nature of magneto-dielectric resonance in ferrites and its potential for low-loss H-tunable dielectric resonators, filters, isolators, and phase shifters for the frequency range 18-110 GHz. Potential avenues for enhancing the E-tuning of ferrite devices are also addressed.

Objectives: Angular and linear velocity measurements play an important role in monitoring and controlling the speed of motors used in applications such as conveyors, turbines, robots, automobiles and other moving objects. In the present paper, an inexpensive and portable system for the measurement of rotations per minute (RPM), linear and angular velocities is developed using Texas Instruments Hall effect sensor: DRV5023-Q1 and microcontroller MSP430G2553. Methods/Statistical Analysis: A unipolar Hall sensor switch produces pulses when a tiny magnet is brought in its vicinity. These pulses are counted by using the microcontroller in a fixed time interval and number of pulses per second gives frequency or rotations per second (RPS). From frequency, RPM, angular and linear velocities are computed. Findings: The measured parameters are displayed on LCD. The experimental frequencies are compared with the frequencies measured using commercial frequency meter (PHILIPS PM6624D). The linearity in velocity measurement (RPM) is represented in the form of a graph. Application/Improvement: In the present work an inexpensive and robust system is designed and developed for the linear velocity measurement. Further, the system is portable and works on a single rechargeable 9V battery. Such systems can be used in complex environment also.

Clustering is the procedure of consortium a set of entities in such a manner those similar entities should in the same group. Cluster analysis is not one specific approach, but the general process to be observed. Clustering can be viewed by different algorithms that differ independently, in their view what is meant by a cluster and how to find them perfectly. Popular notions of clusters include groups with minimum distances among the cluster members. The clustering problem has been discussed by researchers in different things with respective domain. It reveals broad scope of clustering and it is very important in the process of data analysis as one step. However, it is very difficult because of the researchers may assume in different contexts. Clustering is one of best approach of data mining and a common methodology for statistical data analysis. It is used in all major domains like Banking, Health care, Robotics, and other disciplines. This paper mainly aims to discuss about limitations, scope, and purpose of different clustering algorithms in a great detail.

Multifunctional materials have attracted considerable interests from both fundamental and practical aspects such as field – effect transistors, electric protection, transducers and biosensors. Herein, we demonstrate the first superior hydrophobic piezoelectric surface based on the polymer blend of polyvinylidene fluoride (PVDF)–polyacrilonitrile (PAN) assisted with functionalized multiwalled nanotubes (MWNTs), obtained by a modified electrospinning method. Typically, β-phase polyvinylidene fluoride (PVDF) is considered as an excellent piezoelectric and pyroelectric material. However, polar β-phase of PVDF exhibits a naturally high hydrophilicity. It is a well-known fact that the wettability of the surface is dominated by two major factors: surface composition and surface roughness. The significant conversions derived by the incorporation of MWNTs, from a nonpolar α-phase to a highly polar β-phase of PVDF, were confirmed by FTIR. Moreover, the effects of MWNTs on the improvement of the roughness and the hydrophobicity of the polymer blend were evaluated by atomic force microscopy (AFM) and contact angle (CA) measurements. The molar free energy of wetting of the polymer nanocomposite decreases with increasing wt% of MWNTs. All molar free energy values for the wetting of PVDF–PAN/MWNTs were negative, which is a characteristic of a non-wettable film. The combination of surface roughness and low-surface-energy modification in the nanostructured composites leads to high hydrophobicity. In particular, the fabrication of superior hydrophobic surfaces not only has fundamental importance but also various possible functional applications in micro- and nano-materials and devices.

To extract knowledge from Data bases Data mining is being used. Data mining is associated with various techniques. In those Clustering is considered to be one of the best approaches. Clustering a huge data set specifically categorical data is difficult and tedious procedure. In this context a proficient method is proposed that is focused on Rough purity for humanizing accuracy of grouping and keeping the unlabeled objects into proper clusters. Data cataloging is a general method in numerical and mixed domain but it is a key setback in categorical domain. To address this problem we proposed an proficient approach for clustering and cataloguing of categorical data. This system is mainly divided into three parts. Initially data will be divided into various groups, secondly clustering algorithm will be applied and finally Drifting is going to be done when ever complete list of objects are new in a group. This is proven with a large data set in detailed manner. This method improves efficiency for cluster cataloguing.

The performance of multi-segments magneto-electric (ME) layered sensors as charge sources has been investigated by using a typical charge amplifier. We found that the intrinsic performance of such sensors consisting of several (namely 3 and 5) segments, is the same whether these segments are connected in parallel or in series. Both, the signal detecting capacity and the intrinsic noise source of ME layered sensors depend on the volume of sensor. We have measured an equivalent magnetic noise of about 1 nT√Hz at 1 Hz and as low as 10 pT√Hz in the white noise region

In industries nonlinear processes elements like conical tank or spherical tank is used for storage or processing of liquids. In this paper conical tank is used for analysis. Mathematically conical tank is a nonlinear due to its shape. The volume changes at every instant due to change in radius. In this paper fractional PI controller is used to maintain the liquid level of the tank at desired level. The performance of fractional order controller is compared with conventional controller for various tuning methods like Zeigler Nichols, Cohen-coon, CHR and Kappa-Tau.

A new synthesis route with high energy ball milling and microwave sintering is used to obtain nanocrystalline BiFeO3 with improved dielectric and magnetic properties. Electrical and magnetic properties are compared with a conventionally sintered microcrystalline BiFeO3. It is found that the dielectric constant is increased more than one order of magnitude, electrical resistivity by six orders of magnitude and remnant polarization value is increased by 4-5 times for nanocrystalline BiFeO3 in comparison to conventionally sintered microcrystalline BiFeO3. Nanocrystalline BiFeO3 is seen to have ferromagnetic behavior whereas microcrystalline BiFeO3 is known to be antiferromagnetic.

A ferromagnetic and piezoelectric layered composite is found to show resonance enhancement of strain mediated magnetoelectric (ME) coupling at frequencies as low as 20 Hz. Samples of Permendur-lead zirconate titanate (PZT) and Metglas-PZT show bending resonance at fr = 120–158 Hz and two-orders of magnitude enhancement in ME voltage. When a tip mass m = 1 – 20 g is placed on the cantilever, fr decreases and levels off at 20 Hz and ME voltage increases by a factor of two. These observations are in agreement with theory. The composite cantilevers are of importance for ultrasensitive low-frequency magnetometers.

In the clustering using Ming-Syan Chen NIR method has deficiency that is importance of data labeling and outlier detection. The Our-NIR method introduced to improve Ming-Syan Chen method. In this paper the newly introduced method is taken for comparison to improve the cluster efficiency. To improve the efficiency of clustering by the sampling techniques. However, with sampling applied, those sampled points that are not having their labels after the normal process. Even though there is straight forward method for numerical domain and categorical data. But still it has a problem that is how to allocate those unlabeled data points into appropriate clusters in efficient manner. In this paper the concept-drift phenomenon is studied, and we first propose an adaptive threshold for outlier detection, which is a playing vital role detection of cluster. Second, probabilistic approaches for detection of cluster are proposed using Our-NIR method. Index Terms—Clustering, concept-drift, threshold, weather prediction

The influence of yttrium (Y) ion substitution on the magneto-mechanical properties of nickel-zinc ferrite (Ni0.7Zn0.3YxFe2-xO4) or NZFO-Y and the power efficiency (η) of magnetoelectric (ME) gyrators consisting of NZFO-Y/Pb(Zr, Ti)O3 layers were studied. X-ray diffraction (XRD) of polycrystalline samples of NZFO-Y indicated that yttrium incorporated into the crystal lattice resulted in an enlargement of the lattice parameter. Also, the density and ionic hopping length were increased, and the porosity was decreased. Together, these resulted in significant changes in the magneto-mechanical coupling (k33,m) and mechanical quality (Qm) factors. It was found that k33,m decreased with the increasing Y content for 0 ≤ x ≤ 0.08, whereas Qm was increased. For x > 0.05, the values of k33,m and Qm were found to be nearly stable with increasing input power density (PD-Ms) up to 47 W/in3. Under this high power driving condition for 20 min, we found that the power conversion stability of ME gyrators was increased with the increasing Y content in the ferrite and that a maximum power conversion efficiency occurred near 77%. These findings offer the potential for ferrite-based ME gyrator applications in power electronic conversion devices.

Ferromagnetic/piezoelectric composites show strong magnetoelectric coupling that is mediated by mechanical forces. This work is on (i) synthesis of functionally-stepped ferrite-ferroelectric composites and (ii) investigations on the magneto-electric (ME) interactions. Studies were performed on sintered samples of nickel cobalt ferrite and lead zirconate titanate (PZT). The grading parameters of interest are the piezomagnetic coefficients, q, and the piezoelectric coefficients, d. The grading in q is accomplished by compositional variation and the grading in d by poling direction. Measurements of the ME coefficient revealed the strongest coupling in functionally graded samples and the weakest for bilayers with homogeneous q and d.

This paper proposed the enhancement of Landsat8 imagery through an Un-decimated Dual-Tree Complex Wavelet Transform (UDT-CWT) based denoising method and modified homographic filter for edge preservation. This work has been extended by estimating several vegetation parameters like Normalized Difference of Vegetation Index (NDVI), Green Normalized Difference Vegetation Index (GNDVI), Modified Soil Adjusted Vegetation Index (MASVI), and Soil & Atmospherically Resistant Vegetation Index (SARVI). Once the estimation of these parameters was done, the effect of noise was verified. Wavelet decomposes the image into frequency subbands and de-noises each subband separately. These subbands help to increase the resolution. The general problem of the homomorphic filter is that it doesn’t enhance the Low-frequency components which also play a key role in estimating Vegetation Indices (VI).So it was modified to enhance the high-frequency components as well as low-frequency details. Monitoring of vegetation parameters using remote sensing is one of the prominent ways in the estimation of crop yield, Land Use Land Cover (LULC), Water resource management, Drought management, etc. The high-resolution image is more preferable than moderate resolution image to retrieve VI. Image denoising and enhancing the spatial resolution helps to retrieve the parameters well and accurate. The proposed algorithm was working on the images of Landsat8.

Multiferroic particulate composites of Ni0.83Co0.15Cu0.02Fe1.9O4-? - NCCF and lead zirconate titanate (PZT) were prepared conventional ceramic method. The generic formulae x NCCF + (1-x) PZT where x = 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6 mole fractions. The presence of two phases in multiferroic was confirmed with XRD technique. The dielectric constant and loss tangent were studied as a function of frequency (100 Hz to 1 M Hz) and temperature (30-500 �C). The piezoelectric coefficient d33 were also studied on these particulate composites. The hysteresis behaviour was studied to understand the magnetic properties such as saturation magnetization (Ms) and magnetic moment (?B). The static magnetoelectric (ME) voltage coefficient was measured as a function of dc magnetic bias field. A high value of ME output (3151 mV/Oe.cm) was obtained in the composite containing 50% highly magnetostrictive ferrite component NCCF - 50% highly piezoelectric ferroelectric component PZT. These multiferroic particulate composites are used as phase shifters, magnetic sensors, cables etc. � 2009 Elsevier B.V. All rights reserved.

This paper proposes a modified Fuzzy C-means clustering algorithm which removes the different types background present in the image automatically. It removes the limitation associated with Fuzzy C-means clustering algorithm such as selection of initial number of clusters by selecting from the co-occurrence matrix. As the co-occurrence matrix represents the repetition of adjacent gray levels, the proposed algorithm selects centroids as the gray levels corresponding to the diagonal elements of the co-occurrence matrix. Some morphological operations were done to the resultant image. The proposed algorithm uniformly removes the background pixels. The performance of the proposed algorithm is measured quantitatively.

A ferrite–ferroelectric bilayer is used in a slot antenna for static magnetic and electric field control of the radiation characteristics of the antenna. A π-type slot antenna with the resonance frequency ranging from 1.5 to 2.7 GHz, depending on the slot length, is studied. A bilayer of yttrium iron garnet (YIG) on gadolinium gallium garnet bonded to lead zirconate titanate (PZT) is used as the magnetoelectric element. Under a static magnetic field H corresponding to the ferromagnetic resonance in the YIG film, a substantial increase in the power transmitted by the antenna is measured. A dc electric field applied to PZT results in a phase shift of the radiated signal, by 220° for 200 V. The radiation patterns of the antenna show directional characteristics. The demonstrated electric and magnetic field control of antenna characteristics is of interest for applications in phased arrays and beam-forming antennas. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:533–535, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27398

Article history:Received 26 July 2011Accepted 26 August 2011Available online xxxxKeywords:MultiferroicsPiezo-electricMagnetic hexaferriteMagneto-electric couplingMultiferroic sensorsMultiferroic composites Magneto-electric (ME) effects in bi-layer multiferroics consisting of single crystal hexagonal SrAl x Fe 12−x O 19 ferrites (hexaferrites, where x=0, 0.8, 1.2) and PbZrTiO 3 (PZT) have been studied. The main objective of thestudy was to determine the effect of the Al doping concentration on the ME coupling. We experimentallydemonstrate that the Al doping improves dramatically the magnetically induced ME voltage. Moreover, ourdata indicatethat theME response isalinear functionofboth acanddcapplied magnetic fields.This isin con-trast to previously reported multiferroic laminates that show a non-linear magneto-electric induced voltageas a function ofthe applied dcmagnetic field.The multiferroic structures reported inthis work have thereforeenhanced functionality because they can linearly operate as a dual ac/dc magnetic field sensors.Crown Copyright © 2011 Published by Elsevier B.V. All rights reserved.

We characterized the magnetomechanical conversion abilities of Ni-Zn ferrite, cobalt ferrite, and Metglas by constructing a magnetic power path with two winding coils. We found that under high power drive, a portion of the mechanical power re-transformed to the magnetic form and was captured by the receiver coil, which resulted in a decrease in the magnetomechanical conversion ability of the coil-magnetostriction structure. This presents an upper limit of the power conversion characteristics of magnetoelectric gyrators. Furthermore, the efficiency of a Metglas/Pb(Zr,Ti)O3 gyrator was characterized by varying the values of the resistive load, magnetic bias, and power density. The maximum measured efficiency for the power transferred across an optimal resistor load was greater than 90% under low drive conditions and 89% with a power density of up to 30 W/in.3

The objective of this paper is to demonstrate how to improve the read stability of the SRAM cell using the read assist technique. SRAM cell stability is the primary concern for the present and future technologies due to process variations like Vt and Vdd scaling, etc. So it requires additional circuit techniques such as write and read to assist to improve the stability of SRAM memories. To accomplish the non-destructive read operation, we need to either weaken the pass transistor or strengthen the pull-up transistor during the read operation. Towards decrease of pass transistor strength, we implemented the lower word line voltage as read assist circuit. The lower word line voltage will help the selected and un-selected columns (for higher column mux options) during a read operation. But during write operation the lowered word line voltage scheme will impact the write operation. So, in order to improve the read margin we used read assist technique at the same time to ensure that write operation is successful we combined the negative bit line write assist scheme along with read assist technique. The proposed assist circuit gain the power and read margin improvement of 10%, 30% respectively. We observed the read margin analysis at process, voltage and temperature corners.