Showing papers by "College of Engineering, Pune published in 2007"
05 Nov 2007
TL;DR: A method that computes a measure of similarity between two given graphs instead of looking for exact isomorphism is proposed, based on comparing feature vectors extracted from the graphs.
Abstract: In this article, we have tried to explore a new hybrid approach which well integrates the advantages of structural and statistical approaches and avoids their weaknesses. In the proposed approach, the graphic symbols are first segmented into high-level primitive like quadrilaterals. Then, a graph is built by utilizing these quadrilaterals as nodes and their spatial relationships as edges. Additional information like relative length of the quadrilaterals and their relative angles with neighbouring quadrilaterals are associated as attributes to the nodes and edges of the graph respectively. However, the observed graphs are subject to deformations due to noise and/or vectorial distortion (in case of hand-drawn images) hence differs somewhat from their ideal models by either missing or extra nodes and edges appearance. Therefore, we propose a method that computes a measure of similarity between two given graphs instead of looking for exact isomorphism. The approach is based on comparing feature vectors extracted from the graphs. The idea is to use features that can be quickly computed from a graph on the one hand, but are, on the other hand, effective in discriminating between the various graphs in the database. The nearest neighbour rule is used as a classifier due to its simplicity and good behaviour
20 citations
20 Jun 2007
TL;DR: NGN would employ a meshed core, having embedded intelligence which would provide scalability, throughput and enhanced revenue generation by providing optimized connection, service, flexibility and efficient network management thus providing class of service (CoS).
Abstract: The technological advancements in telecommunication is forcing a trend towards unification of network & services, setting up a stage for the emergence of Next Generation Network-NGN.NGN is essentially an IP based network that enables any category of customers to receive wide range of services such as voice, data and video over the same network. The service layer in NGN is independent of underlying network and access is enabled across a wide range of broadband technologies, both wireless such as 3G, Wi-Fi, WiMax and wire line such as Copper DSL, cable, fiber etc. A single IP network replaces the different transport networks. The Migration to NGN reduces network and operational complexity resulting in better & reliable service. It offers unrestricted access by users to different service provider .It supports generalized mobility, which will consistent provision of services to users. In migration to NGN security is crucial. In IP based, which is convergent and has open environment, network infrastructure must be flexible and open towards various types of service. The key technique for NGN is scalable video coding and QoS to adapt to the various requirements such as quality, spatial and temporal resolution and bandwidth variation in heterogeneous networks. NGN would employ a meshed core, having embedded intelligence which would provide scalability, throughput and enhanced revenue generation by providing optimized connection, service, flexibility and efficient network management thus providing class of service (CoS). The constant human endeavor to communicate more effectively without any physical & psychological bondage has led to the trend of evolution in telecommunication -NGN.
14 citations
TL;DR: In this paper, a genetic algorithm is employed to search for the parameters like damping ratio and spring constant to achieve an optimum trade off among ride comfort, handling quality, and suspension stroke simultaneously for random input.
Abstract: A novel control scheme for the active suspension in a 4-DOFs half-car model is presented.A force cancellation control scheme is used to isolate the sprung and the unsprung masses.Skyhook damper and virtual damper concepts are employed to stabilise the sprung and unsprungmasses respectively. Road-following springs are applied for the sprung mass to follow the trendof the road surface condition and to maintain the suspension stroke within a reasonable range.For efficiency, genetic algorithm is employed to search for the parameters like damping ratio andspring constant to achieve an optimum trade off among ride comfort, handling quality, andsuspension stroke simultaneously for random input. Computer simulations are performed usingMATLAB software to verify the proposed control scheme and effectiveness of the appliedgenetic algorithm.
11 citations
01 Nov 2007
TL;DR: DCT based feature vector for fingerprint representation and matching is proposed by dividing the transformed image into various blocks, standard deviation is calculated for each block and such 96 standard deviations will form the feature vector used in matching stage.
Abstract: In the fingerprint recognition application utilizing more information other than minutiae is much helpful. In this paper we proposed discrete cosine transform (DCT) based feature vector for fingerprint representation and matching. The transform is applied on the image directly without any preprocessing. By dividing the transformed image into various blocks, standard deviation is calculated for each block and such 96 standard deviations will form the feature vector. This feature vector is used in matching stage. Work is further extended by forming feature vector of 36 standard deviation from mid and high frequency bands of DCT coefficients. Total 8 images per person are captured for 15 individual and training set is prepared with the help of k images where k varies from 1 to 8. Results are checked against remaining images as well as newly captured image of same person. Results are represented in terms of Truly accepted, Falsely accepted and Rejected users. Recognition rate (%) are calculated with different threshold values. In identification mode 100% results are obtained for a typical threshold value.
9 citations
01 Nov 2007
TL;DR: An enhanced vector quantizer (codebook) is designed by selective training of self-organized feature maps network with different images for quality improvement by using lossy compression technique vector quantization.
Abstract: This paper presents compression of color images using vector quantization (VQ). Being vector quantization is lossy compression technique, the quality of the decompressed images is degraded. In order to achieve trade off between quality of compression along with good compression ratio, the vector quantizer must be designed optimally. In this paper, we have designed an enhanced vector quantizer (codebook) by selective training of self-organized feature maps network with different images for quality improvement. The performance is analyzed using various quality measures along with conventionally used PSNR. The vector quantizer is designed for different color spaces such as RGB, HSI, HSV, YCbCr and performance is tested for quality determination. Finally, performance is compared with JPEG in terms of quality and file sizes.
8 citations
01 Feb 2007
TL;DR: In this article, the influence of load, sliding speed, and concentration of SiC on wear rates, coefficient of friction, and rise in bulk temperature was investigated using the factorial analysis method.
Abstract: Abstract The main aim of using the factorial analysis method in the present work was to investigate the influence of parameters viz.: load, sliding speed, and concentration of SiC, so also the combined interaction of these parameters on wear rates, coefficient of friction, and rise in bulk temperature. Pure copper and 10%SiC reinforced copper composites were produced by powder metallurgy route by compaction and then sintered these compact at 860 °C for 2 h in hydrogen sintering furnace. The wear test was carried out on the Cu-SiC composites. Experimental plan of wear test consisted of two load (25 and 65 N) and two sliding speeds (0.6 and 2.4 m/s) for two compositions (Pure Cu and 10 vol% of SiC in copper matrix). The wear tests were implemented on Pin-on-Disc wear test machine as per ASTM G99. Analysis of wear test data was done by 23 factorial method. The relationship of individual and combined interactive parameters was attempted with worn surfaces and XRD in order to explore possible wear mechanisms.
6 citations
16 Apr 2007
5 citations
09 Jul 2007
TL;DR: A relay-free sliding mode controller is applied to design power system stabilizer for demonstrating the availability of the proposed approach to enhance the stability and to improve the dynamic response of the single machine infinite bus (SMIB) system.
Abstract: The paper presents a new method for design of power system stabilizer (PSS) based on relay-free sliding mode control technique. The control objective is to enhance the stability and to improve the dynamic response of the single machine infinite bus (SMIB) system. We apply this relay-free sliding mode controller to design power system stabilizer for demonstrating the availability of the proposed approach.
5 citations
01 Jan 2007
TL;DR: In this paper, the authors describe the porting of RTLinux on various platforms namely ×86 and ARM (advanced RISC machine) and discuss real-time applications running on above platforms.
Abstract: This paper describes the porting of RTLinux on various platforms namely ×86 and ARM (advanced RISC machine). This paper also discusses real-time applications running on above platforms. On ×86 platform, the realtime tasks are written as loadable kernel modules that can be inserted or removed from kernel space by user-space commands. Thus the real-time code can be developed and tested without rebooting the machine hosting the development and execution. On ARM platform, the real-time applications are run as stand-alone applications.
4 citations
01 Dec 2007
TL;DR: Unsharp masking is used to enhance the edge detail information in the degraded document and it is shown that the method improves sharpness of the image with nearly half computational time.
Abstract: In this paper we present a simple and computationally efficient method for document image enhancement We use Unsharp masking to enhance the edge detail information in the degraded document This image is then used to adjust the local threshold for each pixel Proposed method is experimentally compared with Laplacian sign method and the Otsu method It is shown that the method improves sharpness of the image with nearly half computational time
3 citations
01 Nov 2007
TL;DR: This paper proposes computationally efficient registration and robust interpolation for SR image reconstruction and shows the effectiveness of proposed technique, which is computationally fast having clear perspective of real time implementation.
Abstract: The super-resolution (SR) imaging is a process of constructing high resolution image using several shifted low resolution images of the same scene. The process should ideally be fast, and should add sharpness and detail, both at edges and in regions without adding artifacts. SR imaging works in two major phases: registration and interpolation. Existing registration techniques are computationally time consuming. Current interpolation methods suffer from blocking artifacts and also smoothens the edges and is unable to restore high frequency details in image. In this paper we propose a technique to yield a real time color super resolved image from four low resolution color images. We propose computationally efficient registration and robust interpolation for SR image reconstruction. Our technique is computationally fast having clear perspective of real time implementation. Experiments with several test images show the effectiveness of proposed technique.
01 Nov 2007
TL;DR: A new method for iris recognition using the dual tree complex wavelet transform with reliability and performance that the performance is better than some algorithms, so it is promising to be used in a personal identification system.
Abstract: This paper represents a new method for iris recognition using the dual tree complex wavelet transform. For the dual filter tree, we select two linear phase biorthogonal filter sets with odd and even lengths which is used to filter each signal for quantization to 136 byte iris feature codes. Then the Hamming distance is adopted to match two iris codes. In particular, the appropriate scale for each signal is searched for by minimizing the Hamming distance. The experimental results on CASIA database shows reliability and performance that the performance of this method is better than some algorithms, so it is promising to be used in a personal identification system.
01 Jan 2007
TL;DR: In this article, the authors addressed model identification of simple coupled two tanks, which are coupled by a valve and found practically the model by using MATLAB environment, which gives results almost identical to ideal model of plant.
Abstract: A commonly occurring control problem in the chemical process industries is the control of fluid levels in storage tanks, chemical blending and reaction vessels. In this paper we are addressing model identification of simple coupled two tanks, which are coupled by a valve. We have found practically the model by using MATLAB environment, which gives results almost identical to ideal model of plant. Quantitative Feedback Theory (QFT) is a frequency domain design method applied to design a robust controller for this system. We have practically tested this controller with adding disturbances and set point changes in the process. Designed robust QFT controller gives best results inspite of plant uncertainty and disturbances.
TL;DR: In this paper, the size distribution analysis of magnesium carbonate for a batch operation is presented, where a log normal distribution is assumed in calculating the mean size of the crystals and a change of slope in the particle size distribution v suggests a crystal growth rate independent of crystal size.
Abstract: Crystal size distribution analysis of magnesium carbonate for a batch operation is presented. Log normal distribution is assumed in calculating the mean size of the crystals. Change of slope in the particle size distribution v. particle size plot suggests a crystal growth rate independent of crystal size. The order of nucleation process (m) being >4, as correlated by power law kinetics is indicative of nucleation by primary mechanisms. High supersaturation levels are attributed to theses phenomena. Relatively high saturation rates lead to a widening of the metastable region.
01 Jan 2007
TL;DR: In this paper, the authors examined the ability of the Volume of Fluid method (VOF) available in major computational fluid dynamics (CFD) software such as Fluent and used widely in modeling the motion of interfaces in macroscopic systems to model multiphase micro-fluidic systems accurately.
Abstract: Multiphase flows involving the flow of two or more fluids are becoming increasingly important in micro-fluidic systems because of their potential and projected use as micro-reactors, the production and control of emulsion droplets and their use in analytical devices such as the µTAS systems. In this work we examine the ability of the Volume of Fluid method (VOF model) available in major computational fluid dynamics (CFD) software such as Fluent and used widely in modeling the motion of interfaces in macroscopic systems to model multiphase micro-fluidic systems accurately. In contrast to macroscopic systems multiphase flows in micro-fluidic channels tend to be laminar and dominated by surface tension and wall adhesion. We demonstrate the ability of the VOF model to capture the qualitative and quantitative aspects of multiphase flow in micro-fluidic channels by validating its predictions with experimental observations and/or analytical solutions. The problems for which we have validated the VOF model include the classical case of fluid rise in capillaries and formation of droplets due to the flow of immiscible fluids in a T junction. Based on these results we believe that the VOF model is ideally suited to model many micro-fluidic devices involving the flow of two or more immiscible fluids.
01 Dec 2007
TL;DR: In this article, the authors presented the design of two, two-element microstrip antennas array with and without delay lines for beam steering applications, which have been designed and fabricated on substrate epsivr=4.4 and epsvr=2.1 with thickness 1.6 mm and 1.574 mm respectively with center frequency of 2.4 GHz.
Abstract: This paper presents the design of two, two-element microstrip antennas array with and without delay lines for beam steering applications. These two antennas have been designed and fabricated on substrate epsivr=4.4 and epsivr=2.1 with thickness 1.6 mm and 1.574 mm respectively with center frequency of 2.4 GHz. It has been observed that, the antenna without delay line provides the bandwidth 1.891% on epsivr= 2.1 and 2.772% on epsivr= 4.4 substrate. The antennas have also been fabricated and tested. It has been observed that with delay line, the antenna resonant frequency has been shifted to the lower side on both the substrates, with bandwidth 1.877% for Teflon and 2.351% for Glass Epoxy. This shows the bandwidth shrinkage of 0.014% and 0.421% with delay line for Teflon & Glass Epoxy respectively. Also, it shows that the input impedance changes as the beam steers, by using the delay line.
01 Aug 2007
TL;DR: In this paper, a method of auto-correlation processing of the underwater acoustic signals is proposed to detect the bearing and the range of the target without passing on any indication about the submarines on which they are installed.
Abstract: Passive sonar systems are used by submarines to detect the bearing (direction) and the range (distance) of the enemy target without passing on any indication about the submarines on which they are installed. In conventional passive sonar systems, the target is detected by listening to the underwater acoustic signals. Though these systems detect the bearing accurately, they suffer from the drawback of involved and time consuming computations. A method of auto-correlation processing of the underwater acoustic signals as recommended by W.S. Burdic [1] offers a solution to detect the range accurately and speedily. The concept behind this method, the details of the microcontroller based embedded proto model that was developed to prove the concept and the results thereof are presented in this paper.
01 Nov 2007
TL;DR: Simulation results support the claim of four time faster interpolation as compared to conventional methods along with good quality and the use and computational cost of wavelets are addressed.
Abstract: High resolution digital imaging has been one of the most important developments in image processing over last decade. Constructing high resolution image using one or more shifted low resolution images of same scene is referred as super resolution imaging. Super resolution imaging involves registering the input low resolution images and then interpolation to construct high resolution image. Appropriate interpolation plays an important role in super resolution imaging. Wavelet transform has come up as proven valuable tool for super resolution imaging along with other image processing applications. In this paper we have addressed the use and computational cost of wavelets. We take in hand grid based parallel implementation of wavelet based interpolation and put forward for super resolution imaging as a promising solution to speed up the super resolution imaging process. Simulation results support the claim of four time faster interpolation as compared to conventional methods along with good quality.
05 Aug 2007
01 Jan 2007
TL;DR: In this article, the effect of electrical as well as non-electrical machining parameters on performance in wire electro-discharge machining of metal matrix composites (Al/SiCp ) is examined.
Abstract: Non-traditional process like wire electro-discharge machining (WEDM) is found to show a promise for machining metal matrix composites (MMCs) However, the machining information for the difficult-to-machine particle-reinforced material is inadequate This paper is focused on experimental investigation to examine the effect of electrical as well as non-electrical machining parameters on performance in wire electro-discharge machining of metal matrix composites (Al/SiCp ) Taguchi orthogonal arrays were employed to study the effects of combinations of voltage, current, pulse on-time, off-time, and wire speed and wire tension on kerf width and cutting speed Voltage, current, and on-time were found to have significant effect on cutting speed and kerf width The optimum machining parameter combinations were obtained for cutting speed and kerf width separately Further, multi-objective optimization was done using Taguchi-Grey relational analysis The process has been improved with the aid of Grey relational analysis and Taguchi orthogonal array The results have been verified with confirmation experimentsCopyright © 2007 by ASME
TL;DR: In this article, a model identification of interacting coupled two tanks, which are coupled by an orifice, is addressed for the control of fluid levels in storage tanks, chemical blending and reaction vessels.
01 Jan 2007
TL;DR: In this paper, the effect of electrical and nonelectrical machining parameters on performance in wire electro-discharge machining of metal matrix composites (Al/Al2 O3 p) was examined.
Abstract: Non-traditional process like wire electro-discharge machining (WEDM) is found to show a promise for machining metal matrix composites (MMCs). However, the machining information for the difficult-to-machine particle-reinforced material is inadequate. This paper is focused on experimental investigation to examine the effect of electrical as well as nonelectrical machining parameters on performance in wire electro-discharge machining of metal matrix composites (Al/Al2 O3 p). Taguchi orthogonal array was used to study the effect of combination of reinforcement, current, pulse on-time, off-time, servo reference voltage, maximum feed speed, wire speed, flushing pressure and wire tension on kerf width and cutting speed. Reinforcement percentage, current, on-time was found to have significant effect on cutting rate and kerf width. The optimum machining parameter combinations were obtained for cutting speed and kerf width separately.Copyright © 2007 by ASME
01 Dec 2007
TL;DR: In this article, the authors used back propagation (BP) and quick propagation (QP) neural networks for predicting the required process parameters for on-line control of roundness in turning process.
Abstract: The emergence of government legislations in environmental matters has lead to improvements in machining processes in the recent years. Dry machining is one such attempt in which the use of fluids has been minimized. In this sense, the study of dry turning process is important. In a study by Marcos-Barcena et. al. (2005), the macrogeometric deviations (roundness) of UNS A92024 (Al-Cu) cylindrical bars turned dry under specified conditions of imposed cutting (cutting speed and feed) were reported. They established an exponential relation between roundness and the cutting parameters. For the ongoing research related online control of turning process, neural network was selected due to its capability to adapt to changes in surrounding environment. Hence, the relationship established in earlier study has been used for training and comparative study of back propagation (BP) and quick propagation (QP) neural networks. The results show that, overall, BP was the best algorithm for the application tested. The present study serves as an input for predicting the required process parameters for on-line control of roundness in turning process.
Proceedings Article•
06 Nov 2007TL;DR: This paper discusses the fault tolerant spatial controller design with periodic output feedback for a 540 MWe PHWR, modeled to have a 72 order spatial model.
Abstract: This paper discusses the fault tolerant spatial controller design with periodic output feedback for a 540 MWe PHWR. The input signal to the control valve would generally be derived on the basis of zonal power levels sensed by self powered neutron detectors, which have shorter life compared to the operating life of the reactor. Also, due to failure of insulation, the sensor output may be inaccurate. For assuring high degree of reliability of reactor, a control has to be designed such that the power distribution is effectively controlled even if any one of the zonal power signal or/and corresponding actuator has failed. The 540 MWe nuclear reactor is modeled to have a 72 order spatial model. This model having 14 inputs and outputs each, is used to design a fault tolerant spatial controller with the periodic output feedback gains. The results of simulations are presented.
TL;DR: The applications of Fuzzy Logic to cotton grading will offer a new approach to classify ideal, excellent, good, average, below average and poor quality of cotton.
Abstract: This paper describes the applications of Fuzzy Logic (FL) to cotton grading. In order to improve the accuracy obtained by human experts and available testing instruments, this decision making tool will offer a new approach to classify ideal, excellent, good, average, below average and poor quality of cotton. Various quality features like length, strength, maturity, fineness, trash percentage and colour have been taken in to consideration and prepared fuzzy inference system (FIS) to grade cotton in to the categories such as Ideal, Excellent, good, average, below average and poor.
05 Aug 2007