Showing papers by "National Institute of Technology, Karnataka published in 2004"
TL;DR: The paper deals with the classification of cardiac rhythms using an artificial neural network and fuzzy relationships, with a high level of efficacy of the tools used, with an accuracy level of 80–85%
Abstract: The heart rate is a non-stationary signal, and its variation can contain indicators of current disease or warnings about impending cardiac diseases. The indicators can be present at all times or can occur at random, during certain intervals of the day. However, to study and pinpoint abnormalities in large quantities of data collected over several hours is strenuous and time consuming. Hence, heart rate variation measurement (instantaneous heart rate against time) has become a popular, non-invasive tool for assessing the autonomic nervous system. Computer-based analytical tools for the in-depth study and classification of data over day-long intervals can be very useful in diagnostics. The paper deals with the classification of cardiac rhythms using an artificial neural network and fuzzy relationships. The results indicate a high level of efficacy of the tools used, with an accuracy level of 80-85%.
171 citations
TL;DR: In this paper, analytical formulations and solutions to the static analysis of simply supported anti-symmetric angle-ply composite and sandwich plates are presented, which account for the effect of transverse shear deformation and a non-linear variation of inplane displacements with respect to the thickness coordinate.
67 citations
TL;DR: The Results show that spatial domain the interleaving, the %NRMSE was less than 0.25% for 8-bit encoded pixel intensity, and among the frequency domain interleaved methods, DFT was found to be very efficient.
Abstract: Digital watermarking is a technique of hiding specific identification data for copyright authentication. This technique is adapted here for interleaving patient information with medical images, to reduce storage and transmission overheads. The patient information is encrypted before interleaving with images to ensure greater security. The bio-signals are compressed and subsequently interleaved with the image. This interleaving is carried out in the spatial domain and Frequency domain. The performance of interleaving in the spatial, Discrete Fourier Transform (DFT), Discrete Cosine Transform (DCT) and Discrete Wavelet Transform (DWT) coefficients is studied. Differential pulse code modulation (DPCM) is employed for data compression as well as encryption and results are tabulated for a specific example. It can be seen from results, the process does not affect the picture quality. This is attributed to the fact that the change in LSB of a pixel changes its brightness by 1 part in 256. Spatial and DFT domain interleaving gave very less %NRMSE as compared to DCT and DWT domain. The Results show that spatial domain the interleaving, the %NRMSE was less than 0.25% for 8-bit encoded pixel intensity. Among the frequency domain interleaving methods, DFT was found to be very efficient.
61 citations
TL;DR: In this article, the physicochemical characterization of the prepared catalysts provides evidence that Fe2(MoO4)3 is in fact the active phase of the catalyst, and the experimental results of conversion of methanol and selectivity towards formaldehyde for various residence times were studied.
Abstract: Methanol selective oxidation to formaldehyde over a modified Fe-Mo catalyst with two different stoichiometric (Mo/Fe atomic ratio = 1.5 and 3.0) was studied experimentally in a fixed bed reactor over a wide range of reaction conditions. The physicochemical characterization of the prepared catalysts provides evidence that Fe2(MoO4)3 is in fact the active phase of the catalyst. The experimental results of conversion of methanol and selectivity towards formaldehyde for various residence times were studied. The results showed that as the residence time increases the yield of formaldehyde decreases. Selectivity of formaldehyde decreases with increase in residence time. This result is attributable to subsequent oxidation of formaldehyde to carbon monoxide due to longer residence time.
52 citations
TL;DR: A new estimator for evolutionary spectrum (ES) based on short time Fourier transform (STFT) and modified group delay function (GDFM) and its frequency resolution is better than evolutionary periodogram (EP) and STFT and nearer to that of Wigner Ville distribution.
22 citations
TL;DR: In this paper, an attempt is made to assess the influence of wave height, wave period, and berm width on the stability of S-shaped breakwater with reduced (30% reduction in armor stone weight) armor unit weight.
20 citations
11 Dec 2004
TL;DR: A new method for compact storage and transmission of medical images with concealed patient information in noisy environment is evinced and it is elicited that coded systems can perform better than the uncoded systems.
Abstract: A new method for compact storage and transmission of medical images with concealed patient information in noisy environment is evinced. Digital watermarking is the technique adapted here for interleaving patient information with medical images. The patient information, which comprises of text data and signal graph, is encrypted to prevent unauthorized access of data. The latest encryption algorithm (Rijndael) is used for encrypting the text information. Signal graphs (ECG, EEG EMG etc.) are compressed using DPCM technique. To enhance the robustness of the embedded information, the patient information is coded by error correcting codes (ECC) such as (7,4) Hamming, Bose-Chaudhuri-Hocquenghem (BCH) and Reed Solomon (RS) codes .The noisy scenario is simulated by adding salt and pepper (S&P) noise to the embedded image. For different signal to noise ratio (SNR) of the image, bit error rate (BER) and number of character altered (NOCA) for text data and percentage distortion (PDIST) for the signal graph are evaluated. The performance comparison based on the above parameters is conducted for three types of ECC. It is elicited that coded systems can perform better than the uncoded systems.
13 citations
20 Dec 2004
TL;DR: A robust audio-video speech recognition (AVSR) system that allows us to incorporate the coupled hidden Markov model (CHMM) model for fusion of audio and video modalities is presented.
Abstract: Automatic speech recognition (ASR) systems have been able to gain much popularity since many multimedia applications require robust speech recognition algorithms. The use of audio and visual information in the speaker-independent continuous speech recognition process makes the performance of the system better compared to the ones with only the audio information. There has been a marked increase in the recognition rates by the use of visual data to aid the audio data available. This is due to the fact that video information is less susceptible to ambient noise than audio information. In this paper a robust audio-video speech recognition (AVSR) system that allows us to incorporate the coupled hidden Markov model (CHMM) model for fusion of audio and video modalities is presented. The application records the input data and recognizes the isolated words in the input file over a wide range of signal to noise ratio (SNR). The experimental results show a remarkable increase of about 10% in the recognition rate in the AVSR compared to the audio only ASR and 20% compared to the video only ASR for an SNR of 5 dB.
11 citations
20 Dec 2004
TL;DR: In this article, a block based texture segmentation method based on contourlets and the hidden Markov model (HMM) is proposed, which combines HMM-HMT model that models global dependency between the blocks in addition to the local statistics within a block.
Abstract: In this paper, block based texture segmentation is proposed based on contourlets and the hidden Markov model (HMM). Hidden Markov model is combined with hidden Markov tree (HMT) to form HMM-HMT model that models global dependency between the blocks in addition to the local statistics within a block. The HMM-HMT model is modified to use the contourlet transform, a new extension to the wavelet transform that forms a true basis for image representations. The maximum likelihood multiresolution segmentation algorithm is used to handle several block sizes at once. Since the algorithm works on the contourlet transformed image data, it can directly segment images without the need for transforming into the space domain. The experimental results demonstrate the competitive performance of the algorithm on contourlets with that of the other methods and excellent visual performance at small block sizes.The performance is comparable with that of wavelets and is superior at small block sizes.
8 citations
TL;DR: In this article, the microstructure of a solidifying lead free Sn-3.5Ag solder alloy is found to be highly sensitive to the surface condition of the copper substrate.
7 citations
TL;DR: A detailed literature survey was carried out in the area of noise pollution and its control in the mining industry, embracing equipment like from Heavy Earth Moving Machinery (HEMM), compressors, workshops, pneumatic drills, processing plants etc., to know the status and to control the noise.
Abstract: Worldwide, increasingly stringent regulations are coming into force, limiting the exposure of workers to industrial noise. Industrial noise and its consequences are thus growing in importance to employers, local and central government officials, trade unions, occupational hygienists and physicians and insurers. India is not an exception to this. The mining industry in India is facing serious problems over noise due to increasing demand for minerals for which large capacity machines are being deployed producing high noise levels. To know the status and to control the noise, the S&T Department of the Ministry of Coal, Government of India sponsored a research project in the area of noise pollution and its control for opencast projects. To start with, a detailed literature survey was carried out in the area of noise pollution and its control in the mining industry, embracing equipment like from Heavy Earth Moving Machinery (HEMM), compressors, workshops, pneumatic drills, processing plants etc., to know the q...
TL;DR: In this paper, SiC particulate reinforced A356 Al metal matrix composites were laser treated using pulsed Nd-YAG laser beam and the processing was carried out in air atmosphere at varying pulse energy (5 to 20 J) and scan rates (30 to 150 mm/sec).
Abstract: SiC particulate reinforced A356 Al metal matrix composites were laser treated using pulsed Nd-YAG laser beam. The processing was carried out in air atmosphere at varying pulse energy (5 to 20 J) and scan rates (30 to 150 mm/sec). The samples were cut perpendicular to the track and they were characterized using optical microscopy, scanning electron microscopy and X-ray diffraction. Microstructure of laser treated region consists of regular succession of coarse and fine microstructure signifying the presence of low velocity bands. Transition from cellular/columnar dendritic to equiaxed dendritic structure has been observed. Microstructure of samples laser treated with specific energy greater than 13 kJ/cm2 show presence of Al4C3 platelets.
TL;DR: A detailed literature survey was carried out in the area of noise pollution and its control in the mining industry, embracing equipment like from Heavy Earth Moving Machinery (HEMM), compressors, workshops, pneumatic drills, processing plants etc., to know the status and to control the noise as mentioned in this paper.
Abstract: Worldwide, increasingly stringent regulations are coming into force, limiting the exposure of workers to industrial noise. Industrial noise and its consequences is thus growing in importance to employers, local and central government officials, trade unions, occupational hygienists and physicians and insurers. India is not an exception for this. The mining industry in India is facing serious problem of noise due to increasing demand for minerals for which large capacity machines are being deployed producing high noise levels. To know the status and to control the noise, the S&T Department of the Ministry of Coal, Government of India sponsored a research project in the area of noise pollution and its control for opencast projects. To start with, a detailed literature survey was carried out in the area of noise pollution and its control in the mining industry, embracing equipment like from Heavy Earth Moving Machinery (HEMM), compressors, workshops, pneumatic drills, processing plants etc., to know the quan...
01 Jan 2004
TL;DR: This paper deals with the analysis of eight cardiac abnormalities using Auto Regressive (AR), modeling technique and the results are tabulated below for specific example.
Abstract: The electrocardiogram (ECG) is a representative signal containing information about the condition of the heart. The shape and size of the P-QRS-T wave, the time intervals between its various peaks etc may contain useful information about the nature of disease afflicting the heart. However, the human observer can not directly monitor these subtle details. Besides, since bio-signals are highly subjective, the symptoms may appear at random in the time scale. Therefore, the heart rate variability signal is used as the base signal for the highly useful in diagnostics. This paper deals with the analysis of eight cardiac abnormalities using Auto Regressive (AR), modeling technique. The results are tabulated below for specific example.
11 Dec 2004
TL;DR: The HMM-contourlet HMT method provides superior texture segmentation results and excellent visual performance at small block sizes.
Abstract: Contourlets have emerged as a new mathematical tool for image processing and provide compact and decorrelated image representations Hidden Markov modeling (HMM) of contourlet coefficients is a powerful approach for statistical processing of natural images In this paper, we extended the hidden Markov modeling framework to contourlets and combined hidden Markov trees (HMT) with hidden Markov model to form HMM-Contourlet HMT model The model is used for block based multiresolution texture segmentation The performance of the HMM-contourlet HMT texture segmentation method is compared with that of HMM-real HMT and HMM-complex HMT methods The HMM-contourlet HMT method provides superior texture segmentation results and excellent visual performance at small block sizes
01 Jan 2004
TL;DR: The implementation details of the JPEG2000 still image codec on ADSP-BF535 processor based Analog Devices EZ-kit Lite board are presented, and the quality of the results obtained demonstrate the potential of the low-power micro-signal architecture of Blackfin processor as a good choice for embedded multimedia applications.
Abstract: With increasing use of multimedia in everyday life, there is a need not only for better image compression techniques which can be used in a wide range of applications but also for efficient implementation of these compression algorithms on power-efficient platforms. To cater to such needs several compression methodologies have been proposed and standardized. We have implemented, JPEG2000, an emerging standard for still image compression on the Analog Devices Blackfin digital signal processor (DSP). Implementation of still-image compression on programmable DSPs offer several advantages like ease of changing the codec standard, improved value addition by customizing the codec to the target application, scalability in image sizes etc. This paper presents the implementation details of the JPEG2000 still image codec on ADSP-BF535 processor based Analog Devices EZ-kit Lite board, and the quality of the results obtained demonstrate the potential of the low-power micro-signal architecture of Blackfin processor as a good choice for embedded multimedia applications.
TL;DR: A detailed literature survey was carried out in the area of noise pollution and its control in the mining industry, embracing equipment like from Heavy Earth Moving Machinery (HEMM), compressors, workshops, pneumatic drills, processing plants etc., to know the status and to control the noise.
Abstract: Worldwide, increasingly stringent regulations are coming into force, limiting the exposure of workers to industrial noise. Industrial noise and its consequences is thus growing in importance to employers, local and central government officials, trade unions, occupational hygienists and physicians and insurers. India is not an exception for this. The mining industry in India is facing serious problem of noise due to increasing demand for minerals for which large capacity machines are being deployed producing high noise levels. To know the status and to control the noise, the S&T Department of the Ministry of Coal, Government of India sponsored a research project in the area of noise pollution and its control for opencast projects. To start with, a detailed literature survey was carried out in the area of noise pollution and its control in the mining industry, embracing equipment like from Heavy Earth Moving Machinery (HEMM), compressors, workshops, pneumatic drills, processing plants etc., to know the quan...
20 Dec 2004
TL;DR: In this paper, a simulation of parallel plane electrode gap configurations with symmetrical and unsymmetrical supply is presented, and the results indicate that as the plane radius increases the field uniformity increases.
Abstract: The electrode gaps which results in to uniform electric fields are the most widely used gap configurations in assessing dielectric strength. In the present study simulation results of parallel plane electrode gap configurations with symmetrical and unsymmetrical supply are reported. When plane radius of plane electrode is reduced the plane electrode at its extreme case forms a sphere resulting in to sphere gap arrangement. Results in this transition region are reported. The charge simulation method (CSM) is used to compute electric fields; with errors in simulation being less than 0.06% (in potential). Simulation results indicate that as the plane radius increases the field uniformity increases. Non uniformity for a given plane radius depends on the gap spacing. For given gap spacing when the plane radius of the electrode is more than the gap spacing, improvement in uniformity are not significant The unsymmetrical supply results in higher field non-uniformity in the gap. The height of high voltage (H.V.) electrode above the ground plane (designated as parameter "A" in IS 1876-1961 for sphere gaps with vertical electrode arrangement) has shown negligible influence on the electric field distribution in the gap.
Journal Article•
TL;DR: In this article, a simple, rapid and selective complexometric method is proposed for the determination of mercury(II) in the presence of associated metal ions, which works well in the range 4 to 80 mg of mercury with a relative error of less than 0.30%.
Abstract: A simple, rapid and selective complexometric method is proposed for the determination of mercury(II) in the presence of associated metal ions. Mercury(II) is first complexed with an excess of EDTA and the surplus EDTA is titrated against standard zinc sulphate solution at pH 5-6 using xylenol orange indicator. Glutathione is then added to displace EDTA from the Hg-EDTA complex quantitatively and
the EDTA released is back titrated against a standard zinc sulphate solution as before. The method works well in the range 4 to 80 mg of mercury with a relative error of less than 0.30% and a coeffcient of variation of not more than 0.38%. The effect of the presence of various diverse ions has been studied. The method is used for the determination of mercury(II) in its alloys and complexes.
Journal Article•
TL;DR: In this article, the photoresponse of thin cadmium selenide thin films was investigated and it was observed that as-grown films are not photosensitive and that baking in air, especially above 723 K, leads to considerable improvement in the photoconducting properties of the films.
Abstract: Photoconductivity has been studied in cad mium selenide thin films prepared by thermal evaporation in vacuum.
Attempts have been made to correlate the photoresponse with the deposition conditions . It has been observed that as-grown films, irrespective of the cadmium content, are not photosensitive and that baking in air, especially above 723 K, leads to considerable improvement in the photoconducting properties of cadmium selenide films.
20 Dec 2004
TL;DR: This work uses bit error rate, frame error rate simulations and extrinsic information transfer charts to study and compare the performances of M-BCJR and BCJR equalizers on precoded and non-precoded channels, and designs a practical estimator for computing the true LLR's from the extrINSic outputs of the M-bcJR equalizer.
Abstract: Capitalizing on the tremendous performance gains of turbo codes and the turbo decoding algorithm, turbo equalization is an iterative equalization and decoding technique that can achieve equally impressive performance gains for communication systems that send digital data over channels that require equalization, i.e. those which suffer from intersymbol interference (ISI). Turbo equalizers have been shown to be successful in mitigating the effects of inter-symbol interference introduced by partial response modems and by dispersive channels for code rates of R > 1/2. We analyze the performance of iterative equalization and decoding (IED) using an M-BCJR equalizer. We use bit error rate (BER), frame error rate simulations and extrinsic information transfer (EXIT) charts to study and compare the performances of M-BCJR and BCJR equalizers on precoded and non-precoded channels. We predict the BER performance of IED using the M-BCJR equalizer from EXIT charts and explain the discrepancy between the observed and predicted performances.. We show that the true LLR's can be estimated if the conditional distributions of the extrinsic outputs are known and finally we design a practical estimator for computing the true LLR's from the extrinsic outputs of the M-BCJR equalizer.
Posted Content•
TL;DR: In this article, the authors discuss the present situation of selection and management of technology in rural areas and suggest setting up of Local Resource Centres and Technology Development Centres to facilitate better management of information technology in the rural areas.
Abstract: In India a considerable population lies in the rural areas. their economic growth has to be enhanced using the available technology. Many times this is easier to be said than done. We have seen failure of many technologies due to various reasons. Proper selection of technology is an essential prerequisite for the success of it. The selection of technology becomes more difficult inn rural areas compared to urban areas. this paper discusses the present situation of selection and management of technology in rural areas. The study covers technology related to food, housing, health, energy and industry. However greater emphasis is given to technology related to basic needs such as housing and energy. The survey results indicate that there is sufficient scope for improving technological applications especially in the area of housing and energy sector inn rural areas. information tools such as internet need to percolate and popularize at the grass-root level in rural areas. reasons for probable failure of technology in rural areas also are analyzed in conclusion, it is suggested setting up of Local Resource Centres and Technology Development Centres to facilitate better management of technology inn rural areas.