• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.3
• /
• pp.554-562
• /
• 2004

It was recommended for all ship engaged in international voyages to carry the Satellite Emergency position Indicating Radio Beacon according to Global Maritime Distress ＆ Safety System but also it is tending to be diffused to require the satellite EPIRB installed in small vessel such as a fishery boat by domestic regulations of each countries. Otherwise the domestic regulation can't evaluate exactly the compatibility with the satellite system and the performance of the equipment itself required by international regulation. And even if it is required the performing of the performance inspection in accordance with international regulation, it is difficult to grasp the characteristics of equipment by a generalized measuring equipment. Hence this study performed the measurement for the matters related with an wave forms, modulation characteristics, frequency and the power, etc through the design and implementation of the test bench capable of ensuring most of test items regulated by international regulation. Through this study, it has been paved the way being capable of preparation of the standard regarding to transmission repetition period, phase variation and frequency stability related with the system compatibility and in conclusion, it is enable to improve the performance of a main distress communication equipment directly connected with the life of a survivor.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.8
• /
• pp.1752-1758
• /
• 2010

A FM-CW radar is used for the various purposes as a remote sensing device since it has the advantages of the relatively simple implementation and the low probability of signal interception. A FM-CW radar uses the same frequency modulated continuous wave for both transmission and demodulation. Therefore, the received beat frequency represents the range and Doppler information of targets. However, using the conventional FFT method, the degree of accuracy and resolution in the spectrum estimation can be seriously degraded in the detection and tracking of fast moving targets because of the short dwell time. Therefore, in this paper, the model parameter estimation methods called as an autoregressive method is applied to overcome these problems and showed that the improved accuracy and resolution can be obtained for the target range and velocity estimation.

• Journal of Navigation and Port Research
• /
• v.37 no.2
• /
• pp.143-148
• /
• 2013

The aim of this study is to investigate the characteristics on the profile of local ice load acting on side shell of port side in bow part due to broken ice during icebreaking of ships in ice covered waters. The first Korean icebreaking research vessel 'ARAON' had a sea ice field trial in the Arctic Sea during early August, 2010, and the signals due to local ice impact measured from several strain gauges installed at bow part were gathered. It is known that these data with structural response characteristics due to local ice impact have some different characteristics with a typical hydraulic impact pressure - time history. In this study, the time history on the measured signals was analyzed and the characteristic values were presented using non-dimensional parameters.

• The Journal of the Society of Korean Medicine Diagnostics
• /
• v.11 no.2
• /
• pp.1-12
• /
• 2007

Objectives: The aim of the present investigation was to determine whether the finger photoplethysmographic waveform of a healthy young man will become analogous to those of healthy old men when the photoplethysmographic harmonic components in the young man decrease. Methods and Results: The finger photoplethysgmoraphy was measured in 21 old men over the age of 60 years and a young men. We acquired the representative pulse waveform of old man by averaging the finger photoplethysmographic waveforms measured in the old men. after the photoplethysmographic harmonic components in the young man were diminished with notch filtering, we compared the representative pulse waveform of old man and the pulse waveforms of which the harmonic components decreased in the young man. The finger photoplethysmographic waveform of the young man became analogous to those of the old men as the photoplethysmographic harmonic components in the young man were diminished with notch filtering. Conclusions: Decrease of the second harmonic component may be a precondition of typical age-related change of the pulse waveform.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.2
• /
• pp.1348-1354
• /
• 2015

In this paper, chaotic circuit of the voltage controlled Lorentz system for engineering applications has been designed and implemented in an electronic circuit. The proposed circuit consists of MOS variable resistor, multipliers, capacitors, fixed resistors and operational amplifiers. The circuit was analysed by PSPICE program. PSPICE simulation results show that chaotic dynamics of the circuit can be controlled by the MOS variable resistor through time series analysis, frequency analysis and phase diagrams. Also, we implemented the proposed circuit in an electronic hardware system with discrete elements. Measured results of the circuit showed controllability of the circuit using the MOS resistor.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.8
• /
• pp.2110-2116
• /
• 2009

The culture industry very have interested in modern society so that it is a field to be provided opportunity to can benefits of life with health, medical industry. Especially, music industry to have based on popular support has acknowledged as artistic value to can easily approach that expresses a feeling to exist together with popularity, originality. In this paper, we will want to design indicators to evaluate a singer's musical talent to can speak a key part in these music industry. From this, we applied analysis elements of spectrogram to perform in change of vocal tract shape in singer's voice and public voice about identical music, and performed comparison, analysis of two groups to experiment pattern analysis of result waveform. Therefore, we analyzed pattern in change of vocal tract shape choice a popular music using of experiment to collect singer and public voice about identical part with time so that we designed indicator to can evaluate musicality.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.7 no.6
• /
• pp.1180-1184
• /
• 2006

In a speech coding system using excitation source of voiced and unvoiced, it would be a distortion of speech quality in a voiced and an unvoiced consonants in a frame. In this paper, I propose a new multi-pulse coding method make use of V/S/TSIUVC switching and TSIUVC approximation-synthesis method in order to restrict a distortion of speech quality. The TSIUVC is extracted by using the zero crossing rate and individual pitch pulse. And the TSIUVC extraction rate was 91% for female voice and 96.2% for male voice. The important thing is that the frequency information of 0.547kHz below and 2.813kHz above can be made with high quality synthesis waveform within TSIUVC. I evaluated the MPC of V/UV and FBD-MPC of V/S/TSIUVC. As a result, the synthesis speech of FBD-MPC was better in speech quality than the MPC.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.7 no.6
• /
• pp.1004-1011
• /
• 2006

In this study, we have performed a systematic case study on troubles and diagnoses of passenger car's engine based on OBD. We have acquired 1,242 data in order to analysis accurate troubles' causes and apposite diagnoses. 128 data of them are got using OBD apparatus, and the rest of them are collected on related website. As results, distribution on trouble cases shows bad idling(32%), poor acceleration(21%), stop in running(19%), faulty start(11%), inferior fuel economy(9%), and insufficient power(8%) in order of magnitude. And in the systematic cases, it is not difficult to detect troubles in a single part. But we know that special apparatus such as multichannel scanner is needed in complicated troubles. Furthermore we think that the survey is continued in various ways for more systematic case study on troubles and diagnoses.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.12 no.3
• /
• pp.267-275
• /
• 2007

This paper presents about energy input and output modeling for a flywheel energy storage system that can store and supply mechanical energy, which is emerging as one of clean energy sources, and the analysis and control of a PWM inverter system. Moreover, this paper describes flywheel's characteristics related to variations of mechanical and electrical parameters like as voltage and current versus speed characteristics formed as numerical formula and thus simulate behaviour-status of flywheel energy. Also for comparison and analysis between PI control and PDFF control, the modeling, design and analysis to the single-phase full bridge inverter with double loop feedback control is accomplished through numerical description and simulation. Finally, under load condition 0.1[pu], 1[pu]. it is validated that harmonic characteristics for voltage and current wave is controlled within 5% below even dynamics condition.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.1542-1543
• /
• 2007

This paper presents the effect of driving waveform for piezoelectric bend mode inkjet printhead with optimized mechanical design. Experimental and theoretical studies on the applied driving waveform versus jetting characteristics were performed. The inkjet head has been designed to maximize the droplet velocity, minimize voltage response of the actuator and optimize the firing frequency to eject ink droplet. The head design was carried out by using mechanical simulation. The printhead has been fabricated with Si(100) and SOI wafers by MEMS process and silicon direct bonding method. To investigate how performance of the piezoelectric ceramic actuator influences on droplet diameter and droplet velocity, the method of stroboscopy was used. Using the water based ink of viscosity of 11.8 cps and surface tension of 0.025N/m, it is possible to eject stable droplets through 64 nozzles average velocity of 4.05 m/s with standard deviation of 0.06 m/s and average diameter of $29.2\;{\mu}m$ with standard variation of $0.5\;{\mu}m$.