• The KIPS Transactions:PartD
• /
• v.14D no.4 s.114
• /
• pp.381-388
• /
• 2007

Consumers changed to the subject to produce a digital contents as data transmission technique is advanced and a digital machine is diffused variously. Users are interested greatly in a user creative movie (UCM) production among various online contents. The UCM production method which uses the music and picture is the method that users make the UCM more easily. However, the UCM production service has the problem that any association does not exist in the music and picture and that the picture changes according to fixed time interval without the relation at a music rhythm. To solve this problem, we propose the UCM production method which uses a music analysis and picture analysis in the paper. A music analysis finds a picture change time according to the rhythm and a picture analysis finds the association of the picture. A music analysis finds strong parts of the sound which uses Root-Mean-Square (RMS). And a picture analysis classifies the picture as a scenery picture and people picture which uses structure simplicity of the picture(SSP) and face region detection. A picture analysis got correct result of 86.4% in the experiment and we can finds the association at each picture and arranges the sequence which the picture appears. Therefore, if we use a music and picture analysis at the UCM production, users may make natural and efficient movie.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.9 no.2
• /
• pp.303-310
• /
• 2008

We fabricated hydrogenated amorphous silicon(a-Si:H) 140 nm thick film on a $180\;nm-SiO_2/Si$ substrate with an inductively-coupled plasma chemical vapor deposition(ICP-CVD) equipment at $250^{\circ}C$. Moreover, 30 nm-Ni film was deposited with a thermal-evaporator sequently. Then the film stack was annealed to induce silicides by a rapid thermal annealer(RTA) at $200{\sim}500^{\circ}C$ in every $50^{\circ}C$ for 30 minuets. We employed a four-point tester, high resolution X-ray diffraction(HRXRD), field emission scanning electron microscope(FE-SEM), transmission electron microscope(TEM), and scanning probe microscope(SPM) in order to examine the sheet resistance, phase transformation, in-plane microstructure, cross-sectional microstructure evolution, and surface roughness, respectively. We confirmed that nano-thick high resistive $Ni_3Si$, mid-resistive $Ni_2Si$, and low resistive NiSi phases were stable at the temperature of <300, $350{\sim}450^{\circ}C$, and >$450^{\circ}C$, respectively. Through SPM analysis, we confirmed the surface roughness of nickel silicide was below 12 nm, which implied that it was superior over employing the glass and polymer substrates.

• Journal of Korean Physical Therapy Science
• /
• v.12 no.3
• /
• pp.47-58
• /
• 2005

The purpose of this study is to estimate how much the motility of affected and unaffected lower limb respectively would have effects on their ambulation through comparing the difference between their affected and unaffected lower limb and studying the correlation between such difference and their ambulation. In addition, the study also intends to find out remedial measures suitable for improving their ambulation with relevant physical treatment. To do this, a quantitative electromyogram(QEMG) test was done to both quadriceps and hamstring of affected and unaffected lower limb so as to yield IP values. Based on such IP values, RMS(root mean square) values as the total sum of IP values were found with QEMG analysis system (made by Medelec Co.) and then the ambulation depending on the difference in muscular strength were analyzed by ink-foot print method as well as the corresponding statistics were processed by T-test through SPSS. The effect of differences in muscular strength of quadriceps in affected and unaffected limb of hemiplegic patients on their ambulation was also different in each element of ambulation. However, there was not any statistically significant difference (p>.05). The differences in muscular strength of hamstring in unaffected limbs of hemiplegic patients only affect stride length. It was statistically significant. The effect of difference in muscular strength of the hamstring in affected limb of hemiplegic patients on their ambulation was very different between strong and weak group in terms of walking velocity, step per minute, stride and step length, showing statistically significant difference(p<.05). Although there was a difference in the step length of the affected limb, it was not statistically significant(p>.05). For the unaffected hamstring, there were significant differences of stride length between in unaffected limb and in affected limb. For the affected hamstring, there were also significant differences in walking velocity, step per minute, stride and step length. Besides, it was found that the difference of the muscular strength between strong and weak group was at the highest. Thus, the effect of difference in muscular strength on ambulatory factors such as walking velocity, step per minute, stride and step length did not show any statistical significance but differences in affected and unaffected quadriceps. However, it was found that both the difference of stride in unaffected hamstring and the difference of all ambulatory factors except from step length with affected limb had effects on ambulation depending upon muscular strength.

• Korean Journal of Remote Sensing
• /
• v.34 no.1
• /
• pp.1-15
• /
• 2018

Passive microwave sea surface temperatures (SST) were validated in the Northwest Pacific using a total of 102,294 collocated matchup data between Global Precipitation Measurement (GPM) / GPM Microwave Sensor(GMI) data and oceanic in-situ temperature measurements from March 2014 to December 2016. A root-mean-square (RMS) error and a bias error of the GMI SST measurements were evaluated to $0.93^{\circ}C$ and $0.05^{\circ}C$, respectively. The SST differences between GMI and in-situ measurements were caused by various factors such as wind speed, columnar atmospheric water vapor, land contamination near coastline or islands. The GMI SSTs were found to be higher than the in-situ temperature measurements at low wind speed (<6 m/s) during the daytime. As the wind speed increased at night, SST errors showed positive bias. In addition, other factors, coming from atmospheric water vapor, sensitivity degradation at a low temperature range, and land contamination, also contributed to the errors. One of remarkable characteristics of the errors was their latitudinal dependence with large errors at high latitudes above $30^{\circ}N$. Seasonal characteristics revealed that the errors were most frequently observed in winter with a significant positive deviation. This implies that SST errors tend to be large under conditions of high wind speeds and low SSTs. Understanding of microwave SST errors in this study is anticipated to compensate less temporal capability of Infrared SSTs and to contribute to increase a satellite observation rate with time, especially in SST composite process.

• Current Optics and Photonics
• /
• v.2 no.3
• /
• pp.269-279
• /
• 2018

We are currently investigating the feasibility of a 1.6 m telescope with a laser-guide star adaptive optics (AO) system. The telescope, if successfully commissioned, would be the first dedicated adaptive optics observatory in South Korea. The 1.6 m telescope is an f/13.6 Cassegrain telescope with a focal length of 21.7 m. This paper first reviews atmospheric seeing conditions measured over a year in 2014~2015 at the Bohyun Observatory, South Korea, which corresponds to an area from 11.6 to 21.6 cm within 95% probability with regard to the Fried parameter of 880 nm at a telescope pupil plane. We then derive principal seeing conditions such as the Fried parameter and Greenwood frequency for eight astronomical spectral bands (V/R/I/J/H/K/L/M centered at 0.55, 0.64, 0.79, 1.22, 1.65, 2.20, 3.55, and $4.77{\mu}m$). Then we propose an AO system with a laser guide star for the 1.6 m telescope based on the seeing conditions. The proposed AO system consists of a fast tip/tilt secondary mirror, a $17{\times}17$ deformable mirror, a $16{\times}16$ Shack-Hartmann sensor, and a sodium laser guide star (589.2 nm). The high order AO system is close-looped with 2 KHz sampling frequency while the tip/tilt mirror is independently close-looped with 63 Hz sampling frequency. The AO system has three operational concepts: 1) bright target observation with its own wavefront sensing, 2) less bright star observation with wavefront sensing from another bright natural guide star (NGS), and 3) faint target observation with tip/tilt sensing from a bright natural guide star and wavefront sensing from a laser guide star. We name these three concepts 'None', 'NGS only', and 'LGS + NGS', respectively. Following a thorough investigation into the error sources of the AO system, we predict the root mean square (RMS) wavefront error of the system and its corresponding Strehl ratio over nine analysis cases over the worst ($2{\sigma}$) seeing conditions. From the analysis, we expect Strehl ratio >0.3 in most seeing conditions with guide stars.

• Journal of Drive and Control
• /
• v.13 no.2
• /
• pp.10-18
• /
• 2016

A front-end loader (FEL) mounted on an agricultural tractor is one of the most commonly used implements to mechanize routine agricultural tasks. When the FEL is used with a loaded bucket, careful operation is required to maintain safety and avoid spillage when the tractor passes a bump because a change in the gravity center of the tractor due to varied loadings can affect the stability of the tractor. Use of a boom suspension system consisting of accumulators and orifice dampers can be instrumental in reducing pitching vibrations while increasing the handling performance of the FEL-mounted tractor. The objective of this research was to reduce bump shocks by adding an orifice and a flow control valve to the original hydraulic circuit composed solely of accumulators. A simulation study was performed using the SimulationX program to investigate the effects of an accumulator and an orifice-throttle damper on bump shocks. Results showed that the peak pressure on a boom cylinder and the vertical acceleration of a bucket were significantly affected by use of both an accumulator and an orifice damper. In a field test conducted with a 75-kW tractor, the peak pressure of the boom cylinder, and the root mean square (RMS) vertical acceleration of the bucket and seat were reduced by on average, 23.0, 42.2, and 44.9% respectively, as compared to those measured with the original accumulator system, showing that an improved design for the accumulator hydraulic circuit can reduce bump shocks. Further studies are needed to design a tractor suspension system that includes the effects of cabin suspension and tires as well as dynamic analysis.

• Clinical and Experimental Pediatrics
• /
• v.50 no.5
• /
• pp.462-468
• /
• 2007

Purpose : The purpose of this study was to analyze the changes of the late potential of Signal- averaged electrocardiography (SAECG) and Electrocardiography (ECG) parameters during follow up of those who had taken surgical repair of Tetralogy of Fallot (TOF). Methods : Nine patients who had taken surgical repair of TOF since 1985 checked SAECG and standard 12 leads ECG twice in 1999 and 2005 in Kyungpook national university hospital. We evaluated changes of QRS duration, QT interval and JT interval, QRS dispersion, QT dispersion and JT dispersion of standard 12 leads ECG and Filtered QRS (f-QRS), High frequency low amplitude potential (HFLA), Root mean square in terminal 40 ms (RMS) and Mean voltage in terminal 40 ms (MV) of SAECG between in 1999 and 2005. Results : There were significant decrease of JT dispersion ($101.11{\pm}50.11$ vs $71.11{\pm}22.61ms$, P< 0.05) and significant increase of HFLA ($24.67{\pm}13.19$ vs $32.89{\pm}14.21ms$, P<0.05). But there were no significant changes in other parameters. Conclusion : In repaired TOF patients, we evaluated ECG and SAECG to detect possible late complications such as tricuspid regurgitation, right ventricular enlargement, ventricualar arrythmia and sudden death. And there were significant changes of ECG and SAECG in some parameters (JT dispersion, HFLA). But to see the relationships between the changes of these parameters and the long term prognosis, we need to check more patients and longer follow-up.

• Journal of the Korean Society of Radiology
• /
• v.10 no.8
• /
• pp.597-602
• /
• 2016

Recent clinical field utilizes the aluminium filter in order to reduce the low-energy photons. However, the usage of the filter can cause adverse effect on the image quality because of the scattered dose that is generated by X-ray hardening phenomenon. Further, usage of filter with improper thickness can be a reason of dose creep phenomenon where unnecessary exposure is generated towards the patient. In this study, the author evaluated the RMS and the RSD analysis in order to have a quantitative evaluation for the effect of forward scattering dose by the filter on the image. as a result of the study, the FSR and the RSD was increased together with the increasing of thickness of the filter. In this study the RSD means the standard deviation of the mean value is relatively size. It can be understood that the signal-to-noise ratio decreases when the average value is taken as a signal and the standard deviation is judged as a noise. The signal-to-noise ratio can understanding as index of resolution at image. Based on these findings, it was quantitatively verified that there is a correlation of the image quality with the FSR by using an additional filter. The results, a 2.5 mmAl which is as recommended by NCRP in the tube voltage of 70 kVp or more showed the 14.6% on the RSD when the filter was not in used. these results are considered able to be utilized as basic data for the study about the filter to improve the quality of the image.

• Korean Journal of Remote Sensing
• /
• v.28 no.5
• /
• pp.477-487
• /
• 2012

Sea surface winds in the sea off the east coast of Korea were derived from L-band ALOS (Advanced Land Observing Satellite) PALSAR (Phased Array type L-band Synthetic Aperture Radar) data and their characteristics of errors were analyzed. We could retrieve high-resolution wind vectors off the east coast of Korea including the coastal region, which has been substantially unavailable from satellite scatterometers. Retrieved SAR-wind speeds showed a good agreement with in-situ buoy measurement by showing relatively small an root-mean-square (RMS) error of 0.67 m/s. Comparisons of the wind vectors from SAR and scatterometer presented RMS errors of 2.16 m/s and $19.24^{\circ}$, 3.62 m/s and $28.02^{\circ}$ for L-band GMF (Geophysical Model Function) algorithm 2009 and 2007, respectively, which tended to be somewhat higher than the expected limit of satellite scatterometer winds errors. L-band SAR-derived wind field exhibited the characteristic dependence on wind direction and incidence angle. The previous version (L-band GMF 2007) revealed large errors at small incidence angles of less than $21^{\circ}$. By contrast, the L-band GMF 2009, which improved the effect of incidence angle on the model function by considering a quadratic function instead of a linear relationship, greatly enhanced the quality of wind speed from 6.80 m/s to 1.14 m/s at small incident angles. This study addressed that the causes of wind retrieval errors should be intensively studied for diverse applications of L-band SAR-derived winds, especially in terms of the effects of wind direction and incidence angle, and other potential error sources.

• Clinical and Experimental Pediatrics
• /
• v.52 no.12
• /
• pp.1364-1369
• /
• 2009

Purpose : To analyze abnormal ventricular activation in childhood congenital heart disease induced by postoperative changes in ventricular volume and pressure and ventricular scar formation using signal-averaged electrocardiography (SAECG). Methods : Fifty-two patients who had undergone open heart surgery (OHS) were enrolled. Patients were divided into the following 3 groups: right ventricular volume overload (atrial septal defect, group1), left ventricular volume overload (ventricular septal defect, group2), and right ventricular pressure overload (tetralogy of Fallot, group 3). The patients were monitored by standard 12-lead ECG and SAECG before and 2 months after the operation. QRS duration, QT and QTc intervals, filtered QRS (f-QRS), high frequency low amplitude potential (HFLA), and root mean square (RMS) voltage in the terminal 40 ms of SAECG were determined. Results : In the preoperative period, group1 showed significant increase in QRS (P=0.011) compared to those of the other 2 groups. In the postoperative period, group3 showed significant increase in the QTc interval (P=0.004) compared to those in the other 2 groups. SAECG parameters showed no significant differences among the groups in the pre- or postoperative period. Of the 52 patients, 12 (23%) in the preoperative period and 21 (40%) in the postoperative period had at least 1 SAECG abnormality. The prevalence of SAECG abnormalities was significantly higher in the postoperative group 2 and group 3 (preoperative: 20% versus postoperative: 28%, P<0.001, preoperative: 14% versus postoperative: 64%, P<0.001, respectively). Conclusion : Abnormal SAECG patterns may be attributed to postoperative scars, OHS itself, and/or ventricular overload.