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  • Practical Implementation of Second Generation Wavelet Transformation on 2D Images by Transformation Matrixes
    1-6.
    Views:
    48

    To perform second generation wavelet transformation in digital signal processing is a common operation. Most obvious way to carry out this task is by program cycle management. Computational software usually executes direct matrix algebraic operations much faster, compared to cycles. Avoiding organizing cycles, can increase the processing speed by magnitudes. This paper introduces transformation matrixes to execute the key steps of wavelet transformation: filtering and downsampling. By the employment of the described transformational matrixes, wavelet transformation and filtering of two dimensional images or discrete datasets could be easier and faster.

  • The Effect of Air-fuel Equivalence Ratio Change on the Vibration Components of an Internal-combustion Engine
    1-6.
    Views:
    69

    Nowadays the automotive industry and the motor development are one of the most dynamically developing industries. One solution to the diagnostic systems providing reliability is the acoustic and vibration measurement system, which can indicate and predict a variety of malfunctions after signal processing. The purpose of this experiment is to analyze the effect of the air-fuel equivalence ratio on the vibration components of an internal-combustion engine (ICE) which is a part of the in question measurement system. In the focus of the experiments are the analysis of the time signal, its spectra, and the power content of the signal. With the increment of the air-fuel ratio the amplitudes of the measured signal and its spectral amplitudes showed a downward trend as the RMS values. In addition, certain frequency components disappeared during the actuation of the ICE with an electromotor, so the characterization of the combustion could be come to the front.

  • Forearm-attachable EMG-based Wireless Controller
    1-4.
    Views:
    94

    This paper presents the development process starting from a simple electronic module for amplification of EMG signals. During development the tasks to be solved were extended towards the creation of an EMG-base controller that eventually can be connected to a PC. Among the main goals were the simplicity and low cost of production. There are similar devices commercially available, but the main focus was on the whole process of design, testing, fabrication and the exploration of application areas. It was important to use medical recommendations. The device matches the suggestion of SENIAM, except for the resolution of A/D conversion, which is permissible due to the fact that it was not designed for medical purposes. The final version is capable of detecting and amplifying EMG signals, with the appropriate filtering and digitizing procedures for further processing. With the development of wireless communication capabilities, the device which can be attached to the forearm can be used as a USB HID device with a PC. A number of additional applications are also discussed, pointing out the fact that this piece of technology offers a wide range of possibilities.

  • Tool Development for Human Audible Spectrum Compensation
    1-6.
    Views:
    91

    Communication relies on good understanding. Humans relate to each other through visual, audible and tactile communication. It is imperative that the audible communication message reaches the receiver in good conditions, in order to keep a healthy, smooth and understandable speech. There are some disturbances in human speech and communication when hearing damage is present. Nowadays, hearing loss is a frequent injury, caused by noise pollution, daily stress or noisy workplaces. Yet, it can be treated by several ways. This project consists in developing a tool that captures the emitter's voice audible spectrum, filters the noise and other frequencies, and compensates the message, enabling the listener/receiver understanding. The purpose of this research is not aimed to substitute nor compete with hearing aids in the market, which are well-developed, certified and prescribed by Otorhinolaryngology clinicians. The focus of this study is to identify the issues of human hearing loss and to develop an algorithm for hearing compensation by using filtering techniques in a simulated environment applied to a hearing model.

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