Time filter

Source Type

Kumar Singh V.,Indian Institute of Technology Kanpur | Kumar Singh V.,PDPM Indian Institute of Information Technology, Design & Manufacturing | Mazhari B.,Indian Institute of Technology Kanpur
Applied Physics Letters | Year: 2013

Conventional method used for measurement of linearly extrapolated threshold voltage from the slope of I SD vs. VGS characteristics in organic thin film transistors (OTFTs) suffers from the influence of gate dependence of field mobility and its use for comparing different devices can result in anomalous trends. In the present work, an improved method is described, which eliminates the effects of mobility and yields a unique value of threshold voltage. Experimental results obtained with pentacene OTFTs with two different dielectric materials are presented, which show that actual threshold voltage can be very different than the values estimated using the conventional technique. © 2013 AIP Publishing LLC.


Pandey R.K.,PDPM Indian Institute of Information Technology, Design & Manufacturing | Kumar N.,PDPM Indian Institute of Information Technology, Design & Manufacturing
New Astronomy | Year: 2012

The purpose of this paper is to propose an efficient numerical method for solving Lane-Emden type equations arising in astrophysics using Bernstein polynomials. First Bernstein operational matrix of differentiation is derived using Bernstein polynomials and then applied to solve the linear and nonlinear differential equations of Lane-Emden type. Some illustrative examples are given to demonstrate the efficiency and validity of the proposed algorithm. © 2011 Elsevier B.V. All rights reserved.


Kankar P.K.,PDPM Indian Institute of Information Technology, Design & Manufacturing | Sharma S.C.,Indian Institute of Technology Roorkee | Harsha S.P.,Indian Institute of Technology Roorkee
Neurocomputing | Year: 2013

Fault diagnosis of bearings under localized defects is essential in the design of high performance rotor bearing system. Traditionally, fault diagnosis of rolling element bearings is carried out performed by the use of signal processing methods, which assume statistically stationary signal features. This paper presents a feature-recognition system for rolling element bearings fault diagnosis, which utilizes cyclic autocorrelation of raw vibration signals. Cyclostationary analysis of non-stationary signals clearly indicates the appearance of several distinct modulating frequencies. The coefficients of wavelet transform are calculated using six different base wavelets, after calculating cyclic autocorrelation of vibration signals. The base wavelet that maximizes the Energy to Shannon Entropy ratio is selected to extract statistical features from wavelet coefficients. Finally, a comparative study is carried out with the calculated statistical features as input to soft computing techniques. Three soft computing techniques are used for faults classifications, out of which two are supervised techniques i.e. Support vector machine, Artificial Neural Network and other one is an unsupervised technique i.e. Self-Organizing Maps. The Complex Gaussian wavelet is selected based on maximum Energy to Shannon Entropy ratio. The results show that the support vector machine identifies the fault categories of rolling element bearing more accurately and has a better diagnosis performance. © 2013 Elsevier B.V.


Rai P.,PDPM Indian Institute of Information Technology, Design & Manufacturing | Khanna P.,PDPM Indian Institute of Information Technology, Design & Manufacturing
Advances in Intelligent and Soft Computing | Year: 2012

Face is one of the most important biometric traits. By analyzing the face we get a lot of information such as age, gender, ethnicity, identity, expression, etc. A gender classification system uses face of a person from a given image to tell the gender (male/female) of the given person. A successful gender classification approach can boost the performance of many other applications including face recognition and smart human-computer interface. This paper illustrates the general processing steps for gender classification based on frontal face images. In this study, several techniques used in various steps of gender classification, i.e. feature extraction and classification, are also presented and compared. © 2012 Springer-Verlag GmbH.


Kale S.,PDPM Indian Institute of Information Technology, Design & Manufacturing | Kondekar P.N.,PDPM Indian Institute of Information Technology, Design & Manufacturing
IETE Journal of Research | Year: 2015

This work presents a comprehensive study on ambipolar leakage suppression in Ge n-channel Schottky barrier MOSFETs (Ge n-SB MOSFETs). Also, Fermi level pinning due to metal-induced gap states between the metal contact and semiconductor is another constraint in this device, which restricts the modulation of Schottky barrier height. Here, we effectively suppress the ambipolar leakage by employing underlap gate structure over drain-channel junction, in addition with dopant segregation (DS) to depin the Fermi level. We also investigate the influence of the DS layer doping, thickness, and temperature dependence of ambipolar behaviour using two-dimensional numerical device simulations. Copyright © 2015 by the IETE.


Pal V.K.,PDPM Indian Institute of Information Technology, Design & Manufacturing | Tandon P.,PDPM Indian Institute of Information Technology, Design & Manufacturing
International Journal of Advanced Manufacturing Technology | Year: 2013

Abrasive water jet machining (AWJM) is mainly used to through cut materials that are difficult to cut by conventional machining processes. This process may also be used for controlled depth milling (CDM) of materials. This work focuses on making blind pockets of controlled depths for a set of materials with AWJM. The materials used in the present work are AL 6061 alloy, AL 2024, brass 353, titanium (Ti6Al4V), AISI 304 (SS), and tool steel (M2 Rc 20). The effects of the milling depth and material characteristics on milling time are investigated. It is observed that machinability index and mechanical properties of the materials milled play important role in establishing milling time and surface roughness. It is found that traverse speed of AWJ process is lower for the materials with low machinability index and vice versa. Besides, the milling time increases non-linearly as the depth of milling increases due to loss of energy of jet and increase in standoff distance (SOD). © 2012 Springer-Verlag London Limited.


Naugarhiya A.,PDPM Indian Institute of Information Technology, Design & Manufacturing | Kondekar P.N.,PDPM Indian Institute of Information Technology, Design & Manufacturing
Superlattices and Microstructures | Year: 2015

In this paper, we have proposed a novel approach for the selection of high permittivity (Hk) material for the optimum design of Hk vertical double diffused MOS (VDMOS). The optimum design parameters under consideration are geometry, doping concentration and breakdown voltage (BV). We have investigated reliability and sensitivity of the Hk VDMOS using BV and figure-of-merit (FOM) analysis, respectively. Further, we have compared results of Hk VDMOS with superjunction (SJ) VDMOS and conventional VDMOS. The observation clarifies that the higher doping concentration can be used in the drift region of Hk n-pillar when comparing with a SJ VDMOS and conventional VDMOS without affecting the BV. Due to this, the area-specific on-resistance (RonA) of the Hk VDMOS is less as compared to the SJ VDMOS and conventional VDMOS with the same BV. Using FOM, we can select the Hk material for maximum doping concentration and maximum BV with lowest RonA for specific design application of Hk VDMOS. © 2015 Elsevier Ltd. All rights reserved.


Rai P.,PDPM Indian Institute of Information Technology, Design & Manufacturing | Khanna P.,PDPM Indian Institute of Information Technology, Design & Manufacturing
2010 5th International Conference on Industrial and Information Systems, ICIIS 2010 | Year: 2010

In this paper a new approach is proposed to recognize gender from the face image. This approach will detect the face from the given image. Radon and Wavelet Transforms are combined to extract key facial features for each face images of male and female. These features will be used to classify the face images of each pattern. We have compared the DCT extracted face feature with our face feature extracted by Radon and Wavelet Transforms. The experimental result shows that the proposed approach (combination of face detector, radon and wavelet transforms, KNN classifier) achieves better performance. ©2010 IEEE.


Mukherjee B.,PDPM Indian Institute of Information Technology, Design & Manufacturing
2nd International Conference on Signal Processing and Integrated Networks, SPIN 2015 | Year: 2015

In this paper, a novel sierpinski carpet fractal based Photonic Band Gap (PBG) structure has been proposed. Whereas the square lattice shaped PBG consisting of drilled holes of radius r1=0.8 cm placed at a periodicity of p=3 cm, offers a band gap from 1.6 GHz to 1.95 GHz for a dielectric material of εr=9.8, the addition of secondary holes of radius r2=0.15 cm placed at a distance of δ=1 cm, from the central hole offers a wider band gap from 1.64 GHz to 2.04 GHz. This same structure is then investigated at THz frequency range by keeping the ratio of periodicity of holes to the operating wavelength, constant. Thus, the band gap now shifts to 16.4 THz to 20.4 THz. The proposed PBG can offer effective solutions to PBG based optical fibers and nano antennas for THz and optical communication applications. © 2015 IEEE.


Kumar A.,PDPM Indian Institute of Information Technology, Design & Manufacturing | Rafi S.M.,PDPM Indian Institute of Information Technology, Design & Manufacturing | Singh G.K.,Indian Institute of Technology Roorkee
Digital Signal Processing: A Review Journal | Year: 2012

In this work, a hybrid method in frequency domain for design of a linear-phase quadrature mirror filter bank is proposed. The nonlinear least square hybrid method based on Levenberg-Marquardt (LM) and Quasi-Newton (QN) is developed for the design of a low-pass prototype filter whose responses in the passband and stopband are ideal, and the filter bank response at quadrature frequency is 0.707. The proposed method is employed to optimize the quadratic measure of ideal characteristics of the prototype filter and filter bank at quadrature frequency. Performance and effectiveness of the proposed method in terms of peak reconstruction error (PRE), mean squares error in passband and stopband regions, and error in transition band at quadrature frequency are shown through numerical examples and comparison of the results with other existing method. It was found that the proposed method is very simple and easy to implement for QMF bank design problem. © 2012 Elsevier Inc. All rights reserved.

Loading PDPM Indian Institute of Information Technology, Design & Manufacturing collaborators
Loading PDPM Indian Institute of Information Technology, Design & Manufacturing collaborators