Search results for: Random Telegraph Noise
833 A Hybrid Feature Subset Selection Approach based on SVM and Binary ACO. Application to Industrial Diagnosis
Authors: O. Kadri, M. D. Mouss, L.H. Mouss, F. Merah
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This paper proposes a novel hybrid algorithm for feature selection based on a binary ant colony and SVM. The final subset selection is attained through the elimination of the features that produce noise or, are strictly correlated with other already selected features. Our algorithm can improve classification accuracy with a small and appropriate feature subset. Proposed algorithm is easily implemented and because of use of a simple filter in that, its computational complexity is very low. The performance of the proposed algorithm is evaluated through a real Rotary Cement kiln dataset. The results show that our algorithm outperforms existing algorithms.
Keywords: Binary Ant Colony algorithm, Support VectorMachine, feature selection, classification.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1597832 Hardware Description Language Design of Σ-Δ Fractional-N Phase-Locked Loop for Wireless Applications
Authors: Ahmed El Oualkadi, Abdellah Ait Ouahman
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This paper discusses a systematic design of a Σ-Δ fractional-N Phase-Locked Loop based on HDL behavioral modeling. The proposed design consists in describing the mixed behavior of this PLL architecture starting from the specifications of each building block. The HDL models of critical PLL blocks have been described in VHDL-AMS to predict the different specifications of the PLL. The effect of different noise sources has been efficiently introduced to study the PLL system performances. The obtained results are compared with transistor-level simulations to validate the effectiveness of the proposed models for wireless applications in the frequency range around 2.45 GHz.
Keywords: Phase-locked loop, frequency synthesizer, fractional-N PLL, Σ-Δ modulator, HDL models
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3771831 Electrocardiogram Signal Compression Using Multiwavelet Transform
Authors: Morteza Moazami-Goudarzi, Mohammad. H. Moradi
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In this paper we are to find the optimum multiwavelet for compression of electrocardiogram (ECG) signals. At present, it is not well known which multiwavelet is the best choice for optimum compression of ECG. In this work, we examine different multiwavelets on 24 sets of ECG data with entirely different characteristics, selected from MITBIH database. For assessing the functionality of the different multiwavelets in compressing ECG signals, in addition to known factors such as Compression Ratio (CR), Percent Root Difference (PRD), Distortion (D), Root Mean Square Error (RMSE) in compression literature, we also employed the Cross Correlation (CC) criterion for studying the morphological relations between the reconstructed and the original ECG signal and Signal to reconstruction Noise Ratio (SNR). The simulation results show that the cardbal2 by the means of identity (Id) prefiltering method to be the best effective transformation.Keywords: ECG compression, Multiwavelet, Prefiltering.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1692830 Scale-Space Volume Descriptors for Automatic 3D Facial Feature Extraction
Authors: Daniel Chen, George Mamic, Clinton Fookes, Sridha Sridharan
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An automatic method for the extraction of feature points for face based applications is proposed. The system is based upon volumetric feature descriptors, which in this paper has been extended to incorporate scale space. The method is robust to noise and has the ability to extract local and holistic features simultaneously from faces stored in a database. Extracted features are stable over a range of faces, with results indicating that in terms of intra-ID variability, the technique has the ability to outperform manual landmarking.
Keywords: Scale space volume descriptor, feature extraction, 3D facial landmarking
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1495829 Early Installation Effect on the Vibration Generated by Machines
Authors: Maitham Al-Safwani
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Motor vibration issues were analyzed and correlated to poor equipment installation. We had a water injection pump tested in the factory and exceeded the pump vibration limit. Once the pump was brought to the site, its half-size shim plates were replaced with full-size shims plate that drastically reduced the vibration. In this study, vibration data were recorded for several and similar motors run at the same and different speeds. The vibration values were recorded — for two and a half hours — and the vibration readings analyzed to determine when the readings become consistent. This was as well supported by recording the audio noises produced by some machines seeking a relationship between changes in machine noises and machine abnormalities, such as vibration.
Keywords: Vibration, noise, shaft unbalance, shaft misalignment.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 406828 Implementation Issues of Industrial PID Controller and Their Remedies
Authors: C. B. Vishwakarma
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We elaborated the parallel and series Proportional, Integral and Derivative (PID) controllers, which are being used in industries. Various issues, which are very often faced by control engineers while designing the PID controllers for industrial systems are described. The effect of measurement noise on the actuator due to derivative term of a PID controller has been explained in detail. Similarly, proportional kick, derivative kick, saturation tendency of the actuator and reverse phenomena of an industrial process have been summarized. Moreover, we meticulously explained the remedies of the all issues of the parallel industrial PID controller.
Keywords: Band-width limited derivative control, derivative kick, proportional kick, reverse acting controller, series PID controller.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 91827 A High Bitrate Information Hiding Algorithm for Video in Video
Authors: Wang Shou-Dao, Xiao Chuang-Bai, Lin Yu
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In high bitrate information hiding techniques, 1 bit is embedded within each 4 x 4 Discrete Cosine Transform (DCT) coefficient block by means of vector quantization, then the hidden bit can be effectively extracted in terminal end. In this paper high bitrate information hiding algorithms are summarized, and the scheme of video in video is implemented. Experimental result shows that the host video which is embedded numerous auxiliary information have little visually quality decline. Peak Signal to Noise Ratio (PSNR)Y of host video only degrades 0.22dB in average, while the hidden information has a high percentage of survives and keeps a high robustness in H.264/AVC compression, the average Bit Error Rate(BER) of hiding information is 0.015%.Keywords: Information Hiding, Embed, Quantification, Extract
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1886826 A Novel Approach to Image Compression of Colour Images by Plane Reduction Technique
Authors: K.Sowmyan, A.Siddarth, D.Menaka
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Several methods have been proposed for color image compression but the reconstructed image had very low signal to noise ratio which made it inefficient. This paper describes a lossy compression technique for color images which overcomes the drawbacks. The technique works on spatial domain where the pixel values of RGB planes of the input color image is mapped onto two dimensional planes. The proposed technique produced better results than JPEG2000, 2DPCA and a comparative study is reported based on the image quality measures such as PSNR and MSE.Experiments on real time images are shown that compare this methodology with previous ones and demonstrate its advantages.Keywords: Color Image compression, spatial domain, planereduction, root mean square, image restoration
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1621825 A New Method of Combined Classifier Design Based on Fuzzy Neural Network
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To make the modulation classification system more suitable for signals in a wide range of signal to noise rate (SNR), a novel method of designing combined classifier based on fuzzy neural network (FNN) is presented in this paper. The method employs fuzzy neural network classifiers and interclass distance (ICD) to improve recognition reliability. Experimental results show that the proposed combined classifier has high recognition rate with large variation range of SNR (success rates are over 99.9% when SNR is not lower than 5dB).Keywords: Modulation classification, combined classifier, fuzzy neural network, interclass distance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1213824 Elimination of Redundant Links in Web Pages– Mathematical Approach
Authors: G. Poonkuzhali, K.Thiagarajan, K.Sarukesi
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With the enormous growth on the web, users get easily lost in the rich hyper structure. Thus developing user friendly and automated tools for providing relevant information without any redundant links to the users to cater to their needs is the primary task for the website owners. Most of the existing web mining algorithms have concentrated on finding frequent patterns while neglecting the less frequent one that are likely to contain the outlying data such as noise, irrelevant and redundant data. This paper proposes new algorithm for mining the web content by detecting the redundant links from the web documents using set theoretical(classical mathematics) such as subset, union, intersection etc,. Then the redundant links is removed from the original web content to get the required information by the user..Keywords: Web documents, Web content mining, redundantlink, outliers, set theory.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1999823 A Fast HRRP Synthesis Algorithm with Sensing Dictionary in GTD Model
Authors: R. Fan, Q. Wan, H. Chen, Y.L. Liu, Y.P. Liu
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In the paper, a fast high-resolution range profile synthetic algorithm called orthogonal matching pursuit with sensing dictionary (OMP-SD) is proposed. It formulates the traditional HRRP synthetic to be a sparse approximation problem over redundant dictionary. As it employs a priori that the synthetic range profile (SRP) of targets are sparse, SRP can be accomplished even in presence of data lost. Besides, the computation complexity decreases from O(MNDK) flops for OMP to O(M(N + D)K) flops for OMP-SD by introducing sensing dictionary (SD). Simulation experiments illustrate its advantages both in additive white Gaussian noise (AWGN) and noiseless situation, respectively.
Keywords: GTD-based model, HRRP, orthogonal matching pursuit, sensing dictionary.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1910822 A Low Voltage High Linearity CMOS Gilbert Cell Using Charge Injection Method
Authors: Raheleh Hedayati, Sanaz Haddadian, Hooman Nabovati
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A 2.4GHz (RF) down conversion Gilbert Cell mixer, implemented in a 0.18-μm CMOS technology with a 1.8V supply, is presented. Current bleeding (charge injection) technique has been used to increase the conversion gain and the linearity of the mixer. The proposed mixer provides 10.75 dB conversion gain ( C G ) with 14.3mw total power consumption. The IIP3 and 1-dB compression point of the mixer are 8dbm and -4.6dbm respectively, at 300 MHz IF frequencies. Comparing the current design against the conventional mixer design, demonstrates better performance in the conversion gain, linearity, noise figure and port-to-port isolation.Keywords: Mixer, Gilbert Cell, Charge Injection, RFIC, CMOSTechnology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4287821 Capability Investigation of Carbon Sequestration in Two Species (Artemisia sieberi Besser and Stipabarbata Desf) Under Different Treatments of Vegetation Management (Saveh, Iran)
Authors: M. Alizadeh, M. Mahdavi, M.H. Jouri
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The rangelands, as one of the largest dynamic biomes in the world, have very capabilities. Regulation of greenhouse gases in the Earth's atmosphere, particularly carbon dioxide as the main these gases, is one of these cases. The attention to rangeland, as cheep and reachable resources to sequestrate the carbon dioxide, increases after the Industrial Revolution. Rangelands comprise the large parts of Iran as a steppic area. Rudshur (Saveh), as area index of steppic area, was selected under three sites include long-term exclosure, medium-term exclosure, and grazable area in order to the capable of carbon dioxide’s sequestration of dominated species. Canopy cover’s percentage of two dominated species (Artemisia sieberi Besser & Stipa barbata Desf) was determined via establishing of random 1 square meter plot. The sampling of above and below ground biomass style was obtained by complete random. After determination of ash percentage in the laboratory; conversion ratio of plant biomass to organic carbon was calculated by ignition method. Results of the paired t-test showed that the amount of carbon sequestration in above ground and underground biomass of Artemisia sieberi Besser & Stipa barbata Desf is different in three regions. It, of course, hasn’t any difference between under and surface ground’s biomass of Artemisia sieberi Besser in long-term exclosure. The independent t-test results indicate differences between underground biomass corresponding each other in the studied sites. Carbon sequestration in the Stipa barbata Desf was totally more than Artemisia sieberi Besser. Altogether, the average sequestration of the long-term exclosure was 5.842gr/m², the medium-term exclosure was 4.115gr/m², and grazable area was 5.975gr/m² so that there isn’t valuable statistical difference in term of total amount of carbon sequestration to three sites.Keywords: Carbon sequestration, the Industrial Revolution, greenhouse gases, Artemisia sieberi Besser, Stipa barbata Desf, steppic rangelands
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1733820 The Effect of Directional Search Using Iterated Functional System for Matching Range and Domain Blocks
Authors: Shimal Das, Dibyendu Ghoshal
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The effect of directional search using iterated functional system has been studied on four images taken from databases. The images are portioned successively towards smaller dimension. Presented method provides the faster rate of convergence with respect to processing time in the flat region, but the same has been found to be slower at the border of the images and edges. It has also been revealed that the PSNR is lower at the edges and border portions of the image, and it is found to be higher in the uniform gray region, under the same external illumination and external noise environment.Keywords: Iterated functional system, fractal compression, structural similarity index measure, fractal block coding, affine transformations.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 911819 3D Anisotropic Diffusion for Liver Segmentation
Authors: Wan Nural Jawahir Wan Yussof, Hans Burkhardt
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Liver segmentation is the first significant process for liver diagnosis of the Computed Tomography. It segments the liver structure from other abdominal organs. Sophisticated filtering techniques are indispensable for a proper segmentation. In this paper, we employ a 3D anisotropic diffusion as a preprocessing step. While removing image noise, this technique preserve the significant parts of the image, typically edges, lines or other details that are important for the interpretation of the image. The segmentation task is done by using thresholding with automatic threshold values selection and finally the false liver region is eliminated using 3D connected component. The result shows that by employing the 3D anisotropic filtering, better liver segmentation results could be achieved eventhough simple segmentation technique is used.Keywords: 3D Anisotropic Diffusion, non-linear filtering, CT Liver.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1583818 Evolutionary Dynamics on Small-World Networks
Authors: Jan Rychtar, Brian Stadler
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We study how the outcome of evolutionary dynamics on graphs depends on a randomness on the graph structure. We gradually change the underlying graph from completely regular (e.g. a square lattice) to completely random. We find that the fixation probability increases as the randomness increases; nevertheless, the increase is not significant and thus the fixation probability could be estimated by the known formulas for underlying regular graphs.Keywords: evolutionary dynamics, small-world networks
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1225817 On Musical Information Geometry with Applications to Sonified Image Analysis
Authors: Shannon Steinmetz, Ellen Gethner
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In this paper a theoretical foundation is developed to segment, analyze and associate patterns within audio. We explore this on imagery via sonified audio applied to our segmentation framework. The approach involves a geodesic estimator within the statistical manifold, parameterized by musical centricity. We demonstrate viability by processing a database of random imagery to produce statistically significant clusters of similar imagery content.
Keywords: Sonification, musical information geometry, image content extraction, automated quantification, audio segmentation, pattern recognition.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 402816 Experimental Study on the Floor Vibration Evaluation of Concrete Slab for Existing Buildings
Authors: Yong-Taeg Lee, Jun-Ho Na, Seung-Hun Kim, Seong-Uk Hong
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Damages from noise and vibration are increasing every year, most of which are noises between floors in deteriorated building caused by floor impact sound. In this study, the concrete slab measured vibration impact sound for evaluation floor vibration of deteriorated buildings that fails to satisfy with the minimum thickness. In this experimental study, the vibration scale by impact sound was calibrated and compared with ISO and AIJ standard for vibration. The results show that vibration in slab with thickness used in existing building reach human perception levels.
Keywords: Vibration, Frequency, Accelerometer, Concrete slab.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3869815 Efficient CNC Milling by Adjusting Material Removal Rate
Authors: Majid Tolouei-Rad
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This paper describes a combined mathematicalgraphical approach for optimum tool path planning in order to improve machining efficiency. A methodology has been used that stabilizes machining operations by adjusting material removal rate in pocket milling operations while keeping cutting forces within limits. This increases the life of cutting tool and reduces the risk of tool breakage, machining vibration, and chatter. Case studies reveal the fact that application of this approach could result in a slight increase of machining time, however, a considerable reduction of tooling cost, machining vibration, noise and chatter can be achieved in addition to producing a better surface finish.Keywords: CNC machines, milling, optimization, removal rate.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3466814 Fast Algorithm of Infrared Point Target Detection in Fluctuant Background
Authors: Yang Weiping, Zhang Zhilong, Li Jicheng, Chen Zengping, He Jun
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The background estimation approach using a small window median filter is presented on the bases of analyzing IR point target, noise and clutter model. After simplifying the two-dimensional filter, a simple method of adopting one-dimensional median filter is illustrated to make estimations of background according to the characteristics of IR scanning system. The adaptive threshold is used to segment canceled image in the background. Experimental results show that the algorithm achieved good performance and satisfy the requirement of big size image-s real-time processing.Keywords: Point target, background estimation, median filter, adaptive threshold, target detection.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1833813 Properties of a Stochastic Predator-Prey System with Holling II Functional Response
Authors: Xianqing Liu, Shouming Zhong, Fuli Zhong, Zijian Liu
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In this paper, a stochastic predator-prey system with Holling II functional response is studied. First, we show that there is a unique positive solution to the system for any given positive initial value. Then, stochastically bounded of the positive solution to the stochastic system is derived. Moreover, sufficient conditions for global asymptotic stability are also established. In the end, some simulation figures are carried out to support the analytical findings.
Keywords: stochastically bounded, global stability, Holling II functional response, white noise, Markovian switching.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1573812 An Eigen-Approach for Estimating the Direction-of Arrival of Unknown Number of Signals
Authors: Dia I. Abu-Al-Nadi, M. J. Mismar, T. H. Ismail
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A technique for estimating the direction-of-arrival (DOA) of unknown number of source signals is presented using the eigen-approach. The eigenvector corresponding to the minimum eigenvalue of the autocorrelation matrix yields the minimum output power of the array. Also, the array polynomial with this eigenvector possesses roots on the unit circle. Therefore, the pseudo-spectrum is found by perturbing the phases of the roots one by one and calculating the corresponding array output power. The results indicate that the DOAs and the number of source signals are estimated accurately in the presence of a wide range of input noise levels.
Keywords: Array signal processing, direction-of-arrival, antenna arrays, eigenvalues, eigenvectors.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1364811 Study on the Chaotic Cipher Combined with Mersenne Twister
Authors: Daiki Yoshida, Ariyoshi Nakayama, Hirotaka Watanabe, Taichi Sato, Syuhei Kuriyama, Hiroyuki Kamata
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In this study, we propose the chaotic cipher combined with Mersenne Twister that is an extremely good pseudo-random number generator for the secure communications. We investigate the Lyapunov exponent of the proposed system, and evaluate the randomness performance by comparing RC4 and the chaotic cipher. In these results, our proposed system gets high chaotic property and more randomness than the conventional ciphers.
Keywords: Chaos, chaotic property, cipher, Mersenne Twister, Randomness.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1884810 Edge Detection Algorithm Based on Wavelet De-nosing Applied tothe X-ray Image Enhancement of the Electric Equipment
Authors: Fei Xue, Hong Yu, Da-da Wang, Wei Zhang, Rong-min Zou, Xiao-lanCai
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The X-ray technology has been used in non-destructive evaluation in the Power System, in which a visual non-destructive inspection method for the electrical equipment is provided. However, lots of noise is existed in the images that are got from the X-ray digital images equipment. Therefore, the auto defect detection which based on these images will be very difficult to proceed. A theory on X-ray image de-noising algorithm based on wavelet transform is proposed in this paper. Then the edge detection algorithm is used so that the defect can be pushed out. The result of experiment shows that the method which utilized by this paper is very useful for de-noising on the X-ray images.
Keywords: de-noising, edge detection, wavelet transform, X-ray
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1536809 REDUCER – An Architectural Design Pattern for Reducing Large and Noisy Data Sets
Authors: Apkar Salatian
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To relieve the burden of reasoning on a point to point basis, in many domains there is a need to reduce large and noisy data sets into trends for qualitative reasoning. In this paper we propose and describe a new architectural design pattern called REDUCER for reducing large and noisy data sets that can be tailored for particular situations. REDUCER consists of 2 consecutive processes: Filter which takes the original data and removes outliers, inconsistencies or noise; and Compression which takes the filtered data and derives trends in the data. In this seminal article we also show how REDUCER has successfully been applied to 3 different case studies.
Keywords: Design Pattern, filtering, compression.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1484808 Enhancement of Capacity in a MC-CDMA based Cognitive Radio Network Using Non-Cooperative Game Model
Authors: Kalyani J. Kulkarni, Bharat S. Chaudhari
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This paper addresses the issue of resource allocation in the emerging cognitive technology. Focusing the Quality of Service (QoS) of Primary Users (PU), a novel method is proposed for the resource allocation of Secondary Users (SU). In this paper, we propose the unique Utility Function in the game theoretic model of Cognitive Radio which can be maximized to increase the capacity of the Cognitive Radio Network (CRN) and to minimize the interference scenario. Utility function is formulated to cater the need of PUs by observing Signal to Noise ratio. Existence of Nash Equilibrium for the postulated game is established.Keywords: Cognitive Networks, Game Theory, Nash Equilibrium, Resource Allocation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1735807 Digital filters for Hot-Mix Asphalt Complex Modulus Test Data Using Genetic Algorithm Strategies
Authors: Madhav V. Chitturi, Anshu Manik, Kasthurirangan Gopalakrishnan
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The dynamic or complex modulus test is considered to be a mechanistically based laboratory test to reliably characterize the strength and load-resistance of Hot-Mix Asphalt (HMA) mixes used in the construction of roads. The most common observation is that the data collected from these tests are often noisy and somewhat non-sinusoidal. This hampers accurate analysis of the data to obtain engineering insight. The goal of the work presented in this paper is to develop and compare automated evolutionary computational techniques to filter test noise in the collection of data for the HMA complex modulus test. The results showed that the Covariance Matrix Adaptation-Evolutionary Strategy (CMA-ES) approach is computationally efficient for filtering data obtained from the HMA complex modulus test.Keywords: HMA, dynamic modulus, GA, evolutionarycomputation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1563806 Application of Gamma Frailty Model in Survival of Liver Cirrhosis Patients
Authors: Elnaz Saeedi, Jamileh Abolaghasemi, Mohsen Nasiri Tousi, Saeedeh Khosravi
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Goals and Objectives: A typical analysis of survival data involves the modeling of time-to-event data, such as the time till death. A frailty model is a random effect model for time-to-event data, where the random effect has a multiplicative influence on the baseline hazard function. This article aims to investigate the use of gamma frailty model with concomitant variable in order to individualize the prognostic factors that influence the liver cirrhosis patients’ survival times. Methods: During the one-year study period (May 2008-May 2009), data have been used from the recorded information of patients with liver cirrhosis who were scheduled for liver transplantation and were followed up for at least seven years in Imam Khomeini Hospital in Iran. In order to determine the effective factors for cirrhotic patients’ survival in the presence of latent variables, the gamma frailty distribution has been applied. In this article, it was considering the parametric model, such as Exponential and Weibull distributions for survival time. Data analysis is performed using R software, and the error level of 0.05 was considered for all tests. Results: 305 patients with liver cirrhosis including 180 (59%) men and 125 (41%) women were studied. The age average of patients was 39.8 years. At the end of the study, 82 (26%) patients died, among them 48 (58%) were men and 34 (42%) women. The main cause of liver cirrhosis was found hepatitis 'B' with 23%, followed by cryptogenic with 22.6% were identified as the second factor. Generally, 7-year’s survival was 28.44 months, for dead patients and for censoring was 19.33 and 31.79 months, respectively. Using multi-parametric survival models of progressive and regressive, Exponential and Weibull models with regard to the gamma frailty distribution were fitted to the cirrhosis data. In both models, factors including, age, bilirubin serum, albumin serum, and encephalopathy had a significant effect on survival time of cirrhotic patients. Conclusion: To investigate the effective factors for the time of patients’ death with liver cirrhosis in the presence of latent variables, gamma frailty model with parametric distributions seems desirable.
Keywords: Frailty model, latent variables, liver cirrhosis, parametric distribution.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1045805 Identification of Transformer Core Vibrations and the Effect of Third Harmonic in the Electricity Grid
Authors: Setareh Gorji Ghalamestani, Lieven Vandevelde, Jan Melkebeek
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In this work, an experimental technique is applied for the measurements of the vibrations and deformation of a test transformer core. Since the grid voltage contains some higher harmonics, in addition to a purely sinusoidal magnetisation of the core the presence of third harmonic is also studied. The vibrations of the transformer core for points as well as the surface scan of the leg show more deformation in the corners of the leg than the middle of the leg. The influence of the higher harmonic of the magnetisation on the core deformation is also more significant in the corners of the leg. The core deformation shape under a sinusoidal magnetisation with a higher harmonic is more wavy and fluctuating than that under a purely sinusoidal magnetisation.
Keywords: Vibrations and noise, transformer, vibration measurements, laser vibrometer, higher harmonic.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2974804 Puff Noise Detection and Cancellation for Robust Speech Recognition
Authors: Sangjun Park, Jungpyo Hong, Byung-Ok Kang, Yun-keun Lee, Minsoo Hahn
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In this paper, an algorithm for detecting and attenuating puff noises frequently generated under the mobile environment is proposed. As a baseline system, puff detection system is designed based on Gaussian Mixture Model (GMM), and 39th Mel Frequency Cepstral Coefficient (MFCC) is extracted as feature parameters. To improve the detection performance, effective acoustic features for puff detection are proposed. In addition, detected puff intervals are attenuated by high-pass filtering. The speech recognition rate was measured for evaluation and confusion matrix and ROC curve are used to confirm the validity of the proposed system.Keywords: Gaussian mixture model, puff detection and cancellation, speech enhancement.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2222