Electrical & Nuclear Engineering
Preface:
Patent Selections
Acknowledgements to Reviewers:
Two-Dimensional Wavelet and DCT Transforms Applied for Entropic Compression Improvement Using Digital Images
An image processing patent technique for the improvement of entropic compression with digital images has been presented. “Twodimension wavelet transform” (2D-DWT) “two-dimension discrete cosine transform” (2D-DCT) and multi-resolution perfect reconstruction structures with quincunx filter and grid are used for image processing and simulations using MATLAB up to 2-level of analysis and synthesis. The possibility of suppressing the high and middle frequencies components in order to increase compression rates was considered. As a result higher rates of entropic compression were obtained with the application of 2D-DCT after 2D-DWT in the sub-images generated from the multiresolution perfect reconstruction structures. High quality reconstructed images were obtained even when high and middle frequencies components were suppressed.
Low Power FFT Configuration for Sparse Data Reception and its Effect on Image Reconstruction
The output of an N-point FFT (Fast Fourier Transform) is zero at odd positions if its inputs at odd positions with N/2 distance are equal and this property is exploited in order to reduce the power consumed by the FFT circuitry when operating on sparse data. An OFDM (Orthogonal Frequency Division Multiplexing) transceiver with such a configurable FFT is described where undersampling is applied in order to reduce the ADC (Analog Digital Conversion) power and the buffering requirements by up to 25% or even 37.5% if additional FFT properties are exploited. As will be shown in this paper up to 3/8 of the FFT butterfly operations can be deactivated in this case without any effect on the error caused by the undersampling procedure. Deactivating a higher number of FFT operations is also possible with a small error overhead. The reconstruction of the sparse images captured by a surveillance camera as well as X-ray images is also used as case studies demonstrating the use of the proposed method in image transfer applications over OFDM infrastructures. The Normalized Mean Square Error (NMSE) in these case studies is as low as 0.01 if 12.5% of the FFT input samples are omitted by the undersampling process.
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An Innovative Method for Online Power Monitoring in Nuclear Reactors
The monitoring of the power level during nuclear reactors operation is done by instruments which measure the neutron flux. The calibration of this power is carried out by thermal means. Its accurate knowledge is critical to the fuel burnup calculations and mainly to electrical power. Nuclear fuel burning is proportional to the thermal power released by the reactor and is extremely relevant for the calculation of uranium-235 mass burned profile knowledge of fission products the value of the radioactive decay heat the activity and radiotoxicity. The objective of this paper is to present two methods for real time monitoring of nuclear reactor power using thermal processes. These methods have been developed and experimentally validated in the TRIGA nuclear research reactor at Nuclear Technology Development Center – CDTN (Belo Horizonte Brazil) and are the focus of the paper described here. One uses the temperature difference between an instrumented fuel element and the pool water cooling below the reactor core. This method is innovative and the most reliable way of on-line power monitoring of the CDTN TRIGA reactor. For this methodology a patent was deposited at the Brazilian Institute of Industrial Property (INPI) in 2012. The other method consists in real-time monitoring of the steady-state energy balance of the primary and secondary reactor cooling loops. This process is now the standard methodology for power calibration used in the CDTN TRIGA reactor. It also presents the uncertainty analysis for these thermal power measure procedures.
Slag Detection System Based on Infrared Thermography in Steelmaking Industry
When liquid steel is tapped from a basic oxygen furnace (BOF) it is essential to minimize the quantity of slag carry-over because the high level slag may result in the oxidation and the phosphorus reversion during the secondary metallurgy process. The system with the infrared thermal camera is widely used to detect the slag. However two problems still exist. The first problem is the tracking of tapping stream. The second problem is to automatically discriminate between the slag and the steel according to their different infrared emissivities. In this paper a system used to inspect the slag content is designed. A method that can quickly identify and track the tapping stream is proposed to only measure slag from the area identified as the stream. This reduces any errors caused by background heat sources in the field of view. A method to discriminate between the slag and steel is also proposed. Experimental results prove that the quantity of slag carry-over is decreased with using the system.
On the Feasibility of Optimum-Path Forest in the Context of Internet-of-Things-Based Applications
The “Internet-of-Things" (IoT) paradigm has been extensively focused in the last years since it covers a wide scope of applications that range from spam detection in e-mail datasets to on-body sensors. However this data flooding also known as “big data" phenomenon has required high levels of security since private and important data are now surfing over our heads. In this paper we introduced a recently developed pattern recognition technique called Optimum-Path Forest (OPF) for the task of data mining in IoT-oriented applications such as spam detection in e-mail- and web-content as well as intrusion detection in computer networks. An extensive comparison against fourteen classification techniques can drive us a picture about the effectiveness and efficiency of OPF classifier in that context.
Signal Processing for Fiber Optic Systems
This paper reviews the digital signal processing (DSP) methods used in coherent fiber optic communication systems. With the advances in high speed DSP linear impairments such as chromatic dispersion (CD) and polarization mode dispersion (PMD) can be compensated for using fixed/adaptive equalizers. It is also possible to compensate for the interplay between dispersion and nonlinearity by digital back propagation (DBP) in which the virtual fibers whose signs of dispersion loss and nonlinear coefficients are opposite of those of the transmission fiber are realized in the digital domain by numerically solving the nonlinear Schrdinger equation (NLSE). DSP equalization enhances the transmission performance and error-free reach of coherent fiber optic systems significantly.
A Method of Loudspeaker’s Pure Tone Fault Detection Based on Time-Frequency Image Fractal
Mostly pure tone fault of loudspeakers in the world is detected by human hearing. Obviously the accuracy could not be guaranteed due to subjectivity and it is easy to cause auditory fatigue. Based on the characteristics of loudspeaker’s pure tone detection we propose that the response signal of frequency sweep can be converted into two-dimension timefrequency image signal to enhance the characteristics of fault information through wavelet packet transform. Then time-frequency images are pretreated into contours by binarization and edge extraction. The boxcounting dimensions of time-frequency image by image fractal method is proposed and regarded as the fault characteristics for loudspeaker detection. Through the verification of on-line experiments in workshop the fractal dimension which regarded as complexity of the time-frequency image contours can be the feature for failure determination and the fault identification accuracy rate can reach 95%. It fully meets the requirements of loudspeakers fault detection on-line and better than other recent patents.
An Intelligent Based Motion Estimation with Initial Search Center Prediction
Block matching motion estimation is a popular method in developing video coding applications. The use of fixed pattern prevents the motion estimation algorithms from locating the actual position of the global distortion minimum. Hence to address the problem of local optima in motion estimation it can be viewed as an optimization process to find the best matching block with reduced number of search points which is solved by the PSO technique. Due to the center biased nature of the videos the proposed approach uses an initial pattern to speed up the convergence of the algorithm. To further improve the performance an initial search center prediction and early termination are integrated with pattern based PSO. Simulation results show that the proposed approach has significantly reduced the number of search points when compared to other fixed pattern fast block matching algorithms without degradation in quality. In this paper we have considered several recent patents “Motion estimation methods and systems in video encoding for battery-powered appliances” “Motion estimation for mobile device user interaction” “Simple next search position selection for motion estimation iterative search”.
Acknowledgements to Reviewers:
Patent Selections:
Tyre Pressure Monitoring System - Machine Learning Approach
The THREAD Act (Transportation Recall Enhancement Accountability and Documentation) mandated the use of a suitable tyre pressure monitoring system (TPMS) technology in all light motor vehicles under 5 tons. In the United States as of 2008 and the European Union as of November 1 2012 all new passenger car models released must be equipped with a TPMS. This would alert drivers of under-inflation events. Many countries followed the adoption of TPMS into vehicles. The existing systems depend on pressure sensors strapped on the rim of the tyre. These sensors read the pressure information inside the tyre and transmit it to the receiver in the car. Some systems depend on wheel speed data from the wheel speed sensor. A difference in wheel speed would trigger an alarm based on the algorithm implemented. This paper proposes a new method to monitor tyre pressure by utilising the machine learning approach. Vertical vibrations are extracted from a wheel hub of a moving vehicle using an accelerometer and are classified using machine learning techniques. Statistical features are used to represent the data in the signal. The logistic model tree (LMT) was used as the classifier and attained an accuracy of 92.5% with 10 fold cross validation and 98.5 when tested.
Comparison of Chemometric Algorithms for Multicomponent Analyses and Signal Processing: An Example from 4-(2- Pyridylazo) Resorcinol-Metal Colored Complexes
Chemometrics a relatively young area of analytical chemistry involves extracting meaningful information from experimental data by utilizing mathematical statistical and computational methods with the ultimate goal of evaluating and interpreting analytical data or signals. In this article we provide a comparison of the performance of various chemometrics techniques using data obtained from the colored complexes formed between the ligand 4-(2-pyridylazo)resorcinol (PAR) and zinc copper nickel manganese and cobalt metals. Using a reduced Box-Behnken experimental design we developed calibration models (n=15) and compared the performance of partial least squares (PLS) principal component regression (PCR) multiple linear regression (MLR) (K-matrix) and ridge regression (RR) chemometric techniques in an independent test set (n=7). Our results show that PLS mostly outperformed the other techniques in almost all metal components in the test set. This article provides an overview of various multivariate regression techniques used in chemometrics and provides a comparison of their performance for multi-analyte detection. A discussion of some recently developed multivariate regression techniques in chemometrics as well as challenges and future directions in this field are also discussed.
State Prediction of Bearing Based on Relevance Vector Regression Algorithm with RBF Kernel
The scientific and accurate prediction for state of bearing is the key to ensure its safe operation. A rotating bearing monitoring system was presented in U.S. Patent 7606673 and a bearing condition monitoring apparatus was presented in U.S. Patent 8229682 however the system or apparatus lacks state prediction function of bearing. State prediction of bearing based on relevance vector regression algorithm with RBF kernel is proposed in this paper. Kurtosis of bearing vibration signal can excellently reflect the state of bearing so the future state of bearing can be excellently reflected by predicting the kurtosis of bearing vibration signal. Thus kurtosis prediction of bearing vibration signal based on relevance vector regression algorithm with RBF kernel is studied. Finally the experiments are adopted to demonstrate the feasibility of the proposed method for state prediction of bearing.
Effects of Photon Losses on Fluorescence Lifetime Imaging Microscopy (FLIM) System Optimization
Several approaches for optimization of fluorescence lifetime imaging microscopy (FLIM) system have been recently suggested. This paper discusses the influences of photons losses on the optimization of FLIM systems based time-correlated single photon counting (TCSPC) technique considering the limitations associated with detecting the required amount of photons by the system. The fluorescence intensity (FI) and fluorescence lifetime (FLT) were measured in different operating regimes of the imaging system. The relation between parameters such as excitation power detector gain laser repetition rate is also analyzed. Based on data acquisition limitations of typical TCSPC systems we discuss the considerations for choosing the correct system parameters which would most influence the accuracy of FLIM experiments. A simple scheme for patent optimization of FLIM systems for different types of fluorescent samples is finally suggested.
An Efficient 2D and 3D Palmprint Identification System by Jointly Using Gabor Filter Response, Wavelet Transform and Radial Basis Function
Biometric systems use automated methods for pattern recognition in determining the authenticity of a specific physiological or behavioral characteristic of an individual to determine or verify identity. In this work 2D and 3D palmprints are integrated in order to construct an efficient multi-biometric identification system based on matching score level fusion. In this paper we try to evaluate the usefulness of the 2D and 3D palmprints for improving the palmprint based person identification systems. For that purpose we propose several systems of exploiting the palmprint modalities. In this study the Gabor filter response and the wavelet transform are used for representing the palmprint traits. First the 2D palmprint is filtered by the Gabor filter. The real and imaginary responses of the filtered image are used to create three different vectors. Second the 2D palmprint is transformed into several sub-bands using wavelet transform. After that some sub-bands are used to create several vectors. Subsequently the Radial Basis Function (RBF) is used for modeling and classifying the feature vectors. The results of some classifiers are combined using matching score level fusion strategy. The proposed system was tested and evaluated for its efficacy on the available PolyU 2D and 3D palmprint database of 300 persons. The obtained experimental results show that the system yields the best performance for identifying palmprint and it is able to provide the highest degree of security.
Vibration Based Fault Diagnosis Study of an Automobile Brake System Using K Star (K*) Algorithm – A Statistical Approach
In automobiles the brake system is an essential part responsible for control of the vehicle. Any failure in the brake system generates subsequent catastrophic effects on the vehicle cum passenger’s safety. Hence condition monitoring of the brake system is indispensable. This study focuses on the condition monitoring of a hydraulic brake system through vibration analysis. A machine learning approach was used for this vibration analysis. A hydraulic brake system test rig was fabricated. Frequently occurring fault conditions were simulated. Under good and faulty conditions of a brake system the vibration signals were acquired using a piezoelectric transducer. From the vibration signal statistical features were extracted. The best feature set was identified for classification using attribute evaluator. Selected features were then classified using K Star algorithm. The classification accuracy of such artificial intelligence technique was then compared with the decision tree (DT) and Locally Weighted Learning (LWL) algorithm. Comparative results for fault diagnosis of a hydraulic brake system were reported and discussed. For brake fault diagnosis K Star performs better and it gives the maximum classification accuracy as 98.55%. The model built can be used for condition monitoring of a hydraulic brake system.