Richard Mengko

Digital image processing technique in rock forming minerals identification

In this study, several image processing techniques have been studied for mineral identification. The image data are obtained from a thin section under a polarizing microscope through a video camera with a frame grabber card. The data have been collected for isotropic (garnet), anisotropic non-pleochroic (quartz), and anisotropic pleochroic (biotit) minerals, during parallel- and cross-nicol observation. Using the image processing technique, color analysis can be done by a quantitative method; that is why the optical characteristics and physical phenomena of minerals can be explained more clearly. The end result of this study gives us a promising method for mineral identification using the digital image processing technique.

Performance comparison of denoising methods for heart sound signal

This paper presents the performance analysis and comparison of three denosing methods for heart sound signal based on wavelet transform (WT), total variation (TV), and empirical mode decomposition (EMD). Extensive simulations are performed using normal and abnormal heart sound data and the performance is evaluated in terms of signal-to-noise ratio (SNR), root mean square error (RMSE), and percent root mean square difference (PRD). The simulation results show that EMD based denosing method outperforms two other methods.

Automatic segmentation and detection of heart sound components S1, S2, S3 and S4

In this paper, we propose an automatic segmentation and detection of heart sound components (S1, S2, S3 and S4) which incorporates Empirical Mode Decomposition (EMD) denoising, autocorrelation-based cardiac cycle calculation, Shannon energy envelope extraction, first derivative peak and boundary detection, and real peak selection using Herons formula. The proposed method is evaluated on synthetic data corrupted by white Gaussian noise. The simulation results show that the proposed method is able to segment and identify the heart sound component correctly from normal and abnormal heart sound data.

Extracting blood flow parameters from Photoplethysmograph signals: A review

Infrared sensors are used in Photoplethysmography measurements (PPG) to get blood flow parameters in the vascular system. It is a simple, low-cost non-invasive optical technique that is commonly placed on a finger or toe, to detect blood volume changes in the micro-vascular bed of tissue. The sensor use an infrared source and a photo detector to detect the infrared wave which is not absorbed. The recorded infrared waveform at the detector side is called the PPG signal. This paper reviews the various blood flow parameters that can be extracted from this PPG signal including the existence of an endothelial disfunction as an early detection tool of vascular diseases.

Indonesian text-to-speech using syllable concatenation for PC-based low vision aid

Severe low vision patient cannot read a text clearly. Thus, an instrument engineered for them should have an extra function to read aloud the text. Nowadays, Bahasa Indonesia is still not supported properly in any text to speech modul. This ongoing research is trying to develop an Indonesian text to speech with syllable concatenation. The input of the system comes from a plain text file or manually typed input. This text is then truncated until we get a list of words. The word is then analyzed using brute force algorithm to get proper combination of syllable according to the sound library, which has been recorded previously. Arranged sound then came out from speaker. Test of the system shows that this method works well for any text in Bahasa Indonesia.

Design of ECG Homecare:12-lead ECG acquisition using single channel ECG device developed on AD8232 analog front end

Electrocardiogram (ECG) devices measure electrical activity of the heart muscle to determine heart conditions. ECG signal quality is the key factor in determining the diseases of the heart. However, the availability of ECG devices is causing ECG diagnosis slow and difficult. This paper presents the design of single channel portable ECG device developed on AD8232 chip platform. To extend the capability of an ECG portable device, a 12-lead ECG acquistion technique is also tested out. The results showed the single channel ECG module with additional 12-lead ECG acquisition technique can serve the function of ECG Homecare device, thus making the ECG diagnosis much more accessible.

Design and implementation of 12 Lead ECG signals interpretation system

This paper presents the development of an ECG interpretation software tool that is based on the procedures that is normally done by a medical expert. A set of algorithms is developed here to duplicate the steps that are normally followed manually by a medical expert when analyzing an ECG print out. The software will detect irregularities in the ECG graph and marked it, as a tool to help the medical expert. The experiment is done using the PTB Diagnostic ECG Database (www.physionet.org), and the test is done by comparing its results with the diagnostic notes included in the header of each ECG database file.

Review of digital heart sound classification methods via Artificial Neural Networks

In this paper we discuss three types of Artificial Neural Networks which are commonly used in classification process. Those are Kohonens Self-Organizing Map (SOM), Incremental Self-Organizing Map (ISOM), and Multi-Layer Perception Back Propagation (MLP-BP).

Coherent Modulation Analysis of Photoplethysmographic Signal s by Time -varying Filterbank

Abstract: In spite of its usefulness to early detect cardiovascular disease, photoplethysmographic (PPG) signals are prone to motion artifacts due to its typical measurement locations. These artifacts consequently affect the reliability of systolic peak detection-based PPG parameter calculations. In this paper, the PPG signals are modeled by a small number (3 to 6) of Amplitude-Frequency Modulation (AM-FM) modulated signals such that the synthesis signal preserves its harmonics structure in time-frequency domain. We propose a coherent AM modulating signal detection by which the filterbank tracks Instantaneous Frequency (IF) of each harmonic component. This time-varying filterbank method offers bandwidth preservation of the AM components. Furthermore, the experimental results show that motion artifact (MA) noise reference for the input of the adaptive filter is generated from the corrupted PPG signal itself by using one of applications of our method.

Comparison of Electroencephalography Power Spectral Density between Duramater and Brain Cortex

The intracranial electroencephalography (EEG) or electrocorticography (ECoG) is an invasive type of EEG which its electrodes are placed on the brain surface. It might be increases the amplitude of a recorded brain signal compared with the common EEG due to an impedance reduction. This study tries to analyze the difference by comparing the Power Spectral Density (PSD) of brain signals between duramater and brain cortex. The result shows that there is a distinction between the two sites, where the EEG recorded from brain cortex has a higher PSD than from duramater. Short Research Article Faried et al.; BJAST, 19(2): 1-6, 2017; Article no.BJAST.30908 2