• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.11 no.4
• /
• pp.314-320
• /
• 1998

In this study, we have investigated crystallization properties of $Te_x(Sb_{85}Ge_{15})_{100-x}$ (x=0.3, 0.5, 1.0) thin films prepared by thermal evaporation. The change of reflectance according to phase change from amorphous to crystalline phases with annealing and exposure of diode laser is measured b the n&k analyzer and the surface morphology between amorphous and crystalline phase is analyzed by SEM and AFM. The difference in reflectance($\DeltaR$) between amorphous and crystalline phase appears approximately 20% at the diode laser wavelength, 780nm in all prepared films. Especially, the reflectance difference,$\DeltaR$ comes up to about 30% in $Te_{0.5}(Sb_{85}Ge_{15})_{99.5}$ thin film. Also, amorphous-to-crystalline phase change is observed in all prepared films. As a result of the measurement of the reflectance using diode laser, the reflectance is increased in proportion to the laser power and exposure time in all films. As a result of observing each film with the SEM and AFM, the surface morphology of the annealed and the exposed films are evidently increased than those of as-deposited films. The fast crystallization is occurred by increasing in Te content. Therefore, we conclude that the $Te_{0.5}(Sb_{85}Ge_{15})_{99.5}$ and $Te_1(Sb_{85}Ge_{15})_{99}$ thin films can be evaluated as an attractive optical recording medium with high contast ratio and fast erasing time due to crystallization.

• Broadcasting and Media Magazine
• /
• v.17 no.4
• /
• pp.69-80
• /
• 2012

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2000.10a
• /
• pp.41-48
• /
• 2000

We have installed the borehole seismic recording system at Hyodongri in eastern part of Kyungsan Basin, which has the advantages of reduction in noise by human activities and distorting effects of near-surface rocks. Here we describe briefly the borehole seismic station and recording system. And we analyse the characteistics of back ground the station obtained from borehole sensors. The back ground noise level in time domain is about 50~100$\mu$cm/sec. The average curve of noise spectrum is lower than NHNM(New High Noise Model)of GSN(Global Seismic Network)operated by USGS. The results could be useful prior information for study on earthquake records observed at Hydongri station.

• Proceedings of the KOSOMBE Conference
• /
• v.1998 no.11
• /
• pp.183-184
• /
• 1998

Respiration monitoring is important in many clinical situations due to its relationship to vitality. But present commercial monitoring systems are bulky and expensive, so they are inadequate to be used for long term recording or out-patients application. We have developed a low cost, low power, handhold respiration monitoring system based on airflow measurement. Respiration flow is indirectly detected using a thermister or a themocouple sensor. Real time recording of respiration rate, abnormality detection and apnea alarming are available.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.05a
• /
• pp.160-165
• /
• 2002

The flying height of contact slider is determined by vertical and pitching motions. This paper performed the computer simulation for flying height change of contact slider. It is changed by many parameters, contact stiffness. contact damping, all bearing stiffness ratio and so on. So computer simulation analysis is performed for knowing for what change of these parameters influences in flying height of contact slider. The practical recording zone surface is gotten by using SPM. In recording zone, flying height is simulated for each parameter. the settling time which the flying height of contact slider is lower than 10nm is analyzed over practical disk surface for changing each parameter. Through these results, the contact slider can be analyzed for more accuracy dynamic characteristics.

• Journal of the Optical Society of Korea
• /
• v.1 no.1
• /
• pp.19-22
• /
• 1997

The photorefractive properties of 4% mol magnesium oxide doped lithium niobate have been investigated at room temperature. The recording and erasing time constants were measured as a function of intensity and analyzed by using the two active species (electron-hole) model. The results were used to compute the exposure schedule for multiple hologram recording. We have recorded grating of five holograms by angular multiplexing at room temperature and fixed them by means of a thermal cycling procedure. The highest diffraction efficiency of a fixed grating is up to 50% of an unfixed one.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.3 no.3
• /
• pp.14-21
• /
• 1966

In this article, a recording system for nuclear radiation detection by means of circular radial deflection as an instrument and its applications are described. In the electronic circuit of the instrument, the linearity of a deflected pulse on a circular sweep is especially contribed by employing a multiplying circuit, not to mention the one of a circular time base itself. A sequence of random pulses was recorded on a circular sweep of the CRT screen by means of one cycle unblanking due to a logic circuit. It seems that the intrument is suitable for measuring a decay curve of a short-lived nuclide and its pulse spectrum

• IE interfaces
• /
• v.12 no.2
• /
• pp.174-179
• /
• 1999

This paper describes the development of low cost, miniaturized multi-function image splitter for an unmanned guard system. The essential equipments of an image splitter system consist of a video system which displays in one screen images inputted by several cameras, a frame switcher which records each image sequentially in VTR, and TBC(Time Base Control) system which prevents image flickering during image switching. Currently, the price of similar system on the market is high, system management and repair are difficult, and bulky space is required. Futhermore, since currently available frame switcher can record only 30frame/sec, if eight cameras are installed, each camera image is recorded at the low speed of 3.75frame/sec, and consequently skip some images which may be vital for legal evidence. In this research, we have solved the problem of low speed recording by recording the video screen of splitted images at 30frame/sec and zooming each image when play back.

• Speech Sciences
• /
• v.9 no.1
• /
• pp.17-26
• /
• 2002

Voice onset time (VOT) is defined as the time interval from the oral release of a stop consonant to the onset of glottal pulsing in the following vowel. VOT is a temporal characteristic of stop consonants that reflects the complex timing of glottal articulation relative to supraglottal articulation. There have been many reports on efforts to clarify the acoustical and physiological properties that differentiate the three types of Korean stops, including acoustic, fiberscopic, aerodynamic and electromyographic studies. In the acoustic and fiberscopic studies for stop consonants, the voice onset time and glottal width during the production of stops has been known as the longest and largest in the heavily aspirated type followed by the slightly aspirated type and unaspirated types. The thyroarytenoid and posterior cricoarytenoid muscles were physiologically inter-correlated for differentiating these types of stops. However, a review of the English literature shows that the fine movement of the mucosal edges of the vocal folds during the production of stops has not been well documented. In recent. years, a new method for high-speed recording of laryngeal dynamics by use of a digital recording system allows us to observe with fine time resolution. The movements of the vocal fold edges were documented during the period of stop production using a fiberscopic system of high speed digital images. By observing the glottal width and the visual vibratory movements of the vocal folds before voice onset, the heavily aspirated stop was characterized as being more prominent and dynamic than the slightly aspirated and unaspirated stops.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.05a
• /
• pp.611-613
• /
• 2015

Multimedia classroom teaching as well as the automatic tracking of the camera are automatically saved track to be saved. The existing tracking system is attached to the body by a separate sensor to track or on the front of the sensor to the construction of the track was a hit at the same time in front of the discomfort caused by tracking errors when I had an issue that shouldn't be. In this paper, Microsoft-Kinect sensor, using the speaker's position and behavior analysis (instructor), and PTZ cameras, recording systems, storage classes and lectures with classroom lessons can be effective at the time of recording to the content production about the technology of unmanned speaker tracking solution.