• Phonetics and Speech Sciences
• /
• v.3 no.2
• /
• pp.89-96
• /
• 2011

In this paper, details of the design and implementation of a voice source simulator using Simulink and Matlab are discussed. This simulator is an implementation by model-based design concept. Voice sources can be analyzed and manipulated through various factors by choosing options from GUI input and selecting pre-defined blocks or user created ones. This kind of simulation tool can simplify the procedure of analyzing speech signals for various purposes such as voice quality analysis, pathological voice analysis, and speech coding. Also, basic analysis functions are supported to compare the original signal and the manipulated ones.

• Journal of Biosystems Engineering
• /
• v.26 no.6
• /
• pp.503-508
• /
• 2001

In this paper, time-fiequency analysis and multi-dimensional spectral analysis methods are applied for source identification and diagnosis of non-stationary sound/vibration signals. Sound or vibration problems of general vehicle and agricultural machinary are under 500 Hz. So We used linearly increased chirp signals under 500 Hz. By checking the coherences on concerned time, fur time-variant non-stationary signals, this simulation it very well coincident to expected results.

• Proceedings of the KWS Conference
• /
• 2003.11a
• /
• pp.36-38
• /
• 2003

In order to understand the basic knowledge on the model of heat source in hybrid welding, authors have conducted finite element analysis to calculate heat distribution using three heat source models of non-split type and split type(Volume, Volume-Volume, Volume-Surface). From the research result, we can confirm that Volume-Volume heat source of split type is suitable for the analysis of heat distribution.

• Journal of Korean Society for Atmospheric Environment
• /
• v.19 no.6
• /
• pp.719-731
• /
• 2003

In order to maintain and manage ambient air quality, it is necessary to identify sources and to apportion its sources for ambient particulate matters. The receptor methods were one of the statistical methods to achieve reasonable air pollution strategies. Also, receptor methods, a field of chemometrics, is based on manifold applied statistics and is a statistical methodology that analyzes the physicochemical properties of gaseous and particulate pollutant on various atmospheric receptors, identifies the sources of air pollutants, and quantifies the apportionment of the sources to the receptors. The objective of this study was 1) after obtaining results from the PMF modeling, the existing sources of air at the study area were qualitatively identified and the contributions of each source were quantitatively estimated as well. 2) finally efficient air pollution management and control strategies of each source were suggested. The PMF model was intensively applied to estimate the quantitative contribution of air pollution sources based on the chemical information (128 samples and 25 chemical species). Through a case study of the PMF modeling for the PM-10 aerosols, the total of 11 factors were determined. The multiple linear regression analysis between the observed PM-10 mass concentration and the estimated G matrix had been performed following the FPEAK test. Finally the regression analysis provided quantitative source contributions (scaled G matrix) and source profiles (scaled F matrix). The results of the PMF modeling showed that the sources were apportioned by secondary aerosol related source 28.8 ％, soil related source 16.8％, waste incineration source 11.5%, field burning source 11.0%, fossil fuel combustion source 10%, industry related source 8.3％, motor vehicle source 7.9%, oil/coal combustion source 4.4％, non-ferrous metal source 0.3％. and aged sea- salt source 0.2％, respectively.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.2
• /
• pp.437-444
• /
• 2009

There are many activities that open source software may using at several areas from the government and international organization such as the UN. And Korea enforces the open source software demonstration activities with different meaning link. It is an evaluation field whether or not using the open source software in information projects. But the public information and the education against the open source software are insufficient in the secondary school students who are be latent open source software users. In this paper, We present an examination and analysis of the open source software recognition of the secondary school students in Korea. And We suggest education methods that can use the open source software in the information subject of the revised 7th national education curriculum.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.11 no.3
• /
• pp.391-400
• /
• 1999

The efficiency and capacity of an air source heat pump system decrease as the ambient temperature drops. One strategy of avoiding the decrease of the efficiency and capacity in air source heat pump system is to switch to another thermal energy source. Water can be a good candidate for the heat source. This paper presents the results of the performance analysis of heat pump system with a single unit dual source(SUDS) evaporator The heat exchanger combines two separated evaporators into a single evaporator and the object of the SUDS evaporator is to recover energy from dual heat sources, i.e. air and water. Simulation program is developed for the dual source heat pump system with a SUDS evaporator and experimental data are obtained and compared with the simulation results. Differences in heating capacity and COP are 7% and 8% respectively. Simulation results are in good agreement with the test results. Therefore, the developed program is effectively used for the design and performance prediction of the dual source heat pump system with a SUDS evaporator.

• Korea Journal of Hospital Management
• /
• v.22 no.1
• /
• pp.1-9
• /
• 2017

Purpose : Many studies showed that having a usual source of care improved the efficient access of healthcare service. However in Korea there have been few studies on the usual source of care. So this study aims to find whether having a usual source of care affect the medical utilization and expense. Methodology/Approach : We used the Korean Health Panel data in 2012, 2013 to examine the change of utilization and expenses in ambulatory care affected by having a usual source of care. We selected 1,215 hypertension patients without usual source of care in 2012 and performed linear regression analysis to identify the difference between treatment group(with usual source of care in 2013) and control group(without usual source of care in 2013). Then we performed analysis again separated by the age group. Findings : Among study population, 711(58.5%) reported that they have a usual source of care in 2013. Treatment group reported 1.85 less increase in outpatient visits and 69,234 won less increase in expense than control group with weak significance(visit ${\beta}$ -1.85 p-value 0.0807, expense ${\beta}$ -69,234 p-value 0.0541). People under the age of 65 showed significant change in outpatient visits for tertiary hospital (visit ${\beta}$ -0.78 p-value 0.0154, expense ${\beta}$ -91,462 p-value 0.0168). The analysis which focused outpatient for mild disease showed similar trend. Practical Implications : This study supports the positive effect of having usual source of care which decrease inefficient outpatient utilization. Promoting physician-patient relationships is important for efficiency of healthcare service.

• Journal of Software Assessment and Valuation
• /
• v.17 no.2
• /
• pp.31-38
• /
• 2021

In order to analyze the similarity of the source code object material, the source code on both sides must be able to be compiled and executed. In particular, in the case of hardware-integrated software, it is necessary to check whether the hardware interface matches. However, currently, the source code is provided in an incomplete state which is not original of source code used in developing steps. The complainant confirms that the executing characteristics are similar to their own in the expression and function of the output, and request an evaluation. When a source code compilation error occurs during the evaluation process, the experts draw a flowchart of the source code and applies the method of tracing the code flow for each function as indirect method. However, this method is indirect and the subjective judgment is applied, so there is concern about the contention of objectivity in the similarity evaluation result. In this paper, the problems of unverified source code similarity analysis and improvement directions are dealt with, through the analysis cases of source code disputes applied to embedded systems.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.15 no.5
• /
• pp.807-812
• /
• 2020

This paper proposes a blind speech source separation algorithm using a microphone to separate only the target speech source signal in an environment in which various speech source signals are mixed. The proposed algorithm is a model of frequency domain representation based on independent component analysis method. Accordingly, for the purpose of verifying the validity of independent component analysis in the frequency domain for two speech sources, the proposed algorithm is executed by changing the type of speech sources to perform speech sources separation to verify the improvement effect. It was clarified from the experimental results by the waveform of this experiment that the two-channel speech source signals can be clearly separated compared to the original waveform. In addition, in this experiments, the proposed algorithm improves the speech source separation performance compared to the existing algorithms, from the experimental results using the target signal to interference energy ratio.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.7 no.1
• /
• pp.128-141
• /
• 2015

Independent Component Analysis (ICA), one of the blind source separation methods, can be applied for extracting unknown source signals only from received signals. This is accomplished by finding statistical independence of signal mixtures and has been successfully applied to myriad fields such as medical science, image processing, and numerous others. Nevertheless, there are inherent problems that have been reported when using this technique: instability and invalid ordering of separated signals, particularly when using a conventional ICA technique in vibratory source signal identification of complex structures. In this study, a simple iterative algorithm of the conventional ICA has been proposed to mitigate these problems. The proposed method to extract more stable source signals having valid order includes an iterative and reordering process of extracted mixing matrix to reconstruct finally converged source signals, referring to the magnitudes of correlation coefficients between the intermediately separated signals and the signals measured on or nearby sources. In order to review the problems of the conventional ICA technique and to validate the proposed method, numerical analyses have been carried out for a virtual response model and a 30 m class submarine model. Moreover, in order to investigate applicability of the proposed method to real problem of complex structure, an experiment has been carried out for a scaled submarine mockup. The results show that the proposed method could resolve the inherent problems of a conventional ICA technique.