• Journal of the Korean Society for Precision Engineering
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• v.26 no.11
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• pp.47-54
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• 2009

Spin coaters are the essential instruments in micro-fabrication processes, which apply uniform thin films to flat substrates. In this research, a spin coater diagnosis system is developed to detect the abnormal operation of TFT-LCD process in real time. To facilitate the real-time data acquisition and analysis, the circular-buffered continuous data transfer and the short-time Fourier transform are applied to the fault diagnosis system. To determine whether the system condition is normal or not, a steady-state detection algorithm and a frequency spectrum comparison algorithm using confidence interval are newly devised. Since abnormal condition of a spin coater is rarely encountered, algorithm is tested on a CD-ROM drive and the developed program is verified by a function generator. Actual threshold values for the fault detection are tuned in a spin coater in process.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.10a
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• pp.241-248
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• 1999

Structural damage during an earthquake is caused by the response of the structure to the ground motion input at its base. The dynamic force produced in the structure are due to the inertia of its vibrating elements. The response of the structure exceeds the ground motion and this dynamic magnification depends on the duration and frequency content of the ground vibration, the soil properties at the site, distance from the epicenter and the dynamic characteristics of the structure. Earthquake load used in this study as a input data was artificially simulated with the design spectrum diagram in the Korean Earthquake Resistant Design Code. This paper presents the seismic analysis of the continuous preflex composite girder bridges according to variation of pier's height and span's length.

• Journal of the Optical Society of Korea
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• v.14 no.1
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• pp.49-54
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• 2010

In this study, the use of a continuous-wave (CW) supercontinuum (SC) seeded by an erbium-doped fiber's amplified spontaneous emission (ASE) for optical-coherence tomography imaging is experimentally demonstrated. It was shown, by taking an in-depth image of a human tooth sample, that due to the smooth, flat spectrum and long-term stability of the proposed CW SC, it can be readily applied to the spectral-domain optical-coherence tomography system. The relative-intensity noise level and spectral bandwidth of the CW SC are also experimentally analyzed as a function of the ASE beam power.

• Journal of the Korea Society of Computer and Information
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• v.24 no.2
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• pp.57-66
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• 2019

This paper compared the performance with an overview of channel equalization techniques used in high-speed serial transceivers, including the homogeneous architecture and associated components for the GHz interconnect of backplane and cable channels. It also used the MATLAB tool to present system analysis and simulation results for continuous time equivalent structures. In the case of conventional continuous equalization, high frequency deficits occur due to the use of a comparator that is difficult to implement as well as the low speed limit. In this paper, the channel equalization technique based on the power spectrum analysis of clocks was used to compensate for the frequency loss, and the application of the TX+Channel and TX+Equalizer filters enabled the measurement of attenuation and equivalence without comparators. The application of blender and band-pass filters at high speeds also showed significant effectiveness.

• Proceedings of the KIEE Conference
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• 2005.11a
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• pp.60-61
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• 2005

Electrodes were fabricated on a single ZnO nanowire by photolithography process, metal evaporation, and lift-off. The slow photoresponses of the ZnO nanowire under the continuous illumination of 325nm-wavelength light (corresponding to above-bandgap excitation) indicate that the traps related to oxygen vacancy disturb the flow of electron in ZnO nanowire. The photoresponse and PL spectra were measured, and observed that the excitonic band in the PL spectrum was absent in the photoresponse.

• Journal of Life Science
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• v.14 no.1
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• pp.193-197
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• 2004

A continuous enrichment culture procedure was used to isolate bacteria from various soil sources capable of suppressing large patch disease of turfgrass. Six isolates consistently suppressed large patch in turfgrass, and ranged in the spectrum of extracellular enzymes that they expressed. The best disease- suppressing isolate, TBM912, expressed protease, CMCase, and pectinase activity and inhibited the growth of Rhizectonin solani and Betrytis cinerea in vitro. Here we show that this strain also produces an antibiotic that was identified by TLC, SDS-PACE and HPLC analysis as lipopeptide.

• Science of Emotion and Sensibility
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• v.13 no.3
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• pp.429-440
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• 2010

It is known that as many as 1 in 91 children are diagnosed with an autistic spectrum disorder, and the incidence rate of the autistic spectrum disorder is much higher than that of cancer in Korea. It is necessary to develop a novel technology to sense their emotional status and give proper psychological diagnosis and therapy, since the children with autistic spectrum disorder usually do not express their own emotional status. This article presents the state-of-the-arts on the affective computing technologies that include recognition of emotional status through bio-sensing and virtual affective agent modeling, and then proposes a novel system architecture for diagnosis and therapy of autistic spectrum disorder. The diagnosis and therapy system of autistic spectrum disorder is composed of bio-sensing module, virtual environment module with affective agents, and haptic interface module. The architecture proposed in this paper will enhance the objectivity to diagnose autism spectrum disorders, and enable continuous treatment in daily life.

• Journal of the Korean Society of Radiology
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• v.15 no.1
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• pp.71-78
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• 2021

When continuous X-ray are used when acquiring and X-ray image, even the same material may not be accurately represented in the image according to the thickness due to various X-ray energies. To solve this problem, the X-ray energy spectrum was changed to improve the image quality. Using SPEKTR v3.0, an X-ray energy spectrum with an additional filter added and a general X-ray energy spectrum using only a unique filter were obtained. Simulation was performed using the obtained X-ray energy spectrum as a radiation source for Geant4 Application for Tomographic Emission (GATE). Using GATE data, an X-ray image with an additional filter and an image reconstructed from and X-ray image without an additional filter were compared and analyzed through a mono energy image of 74 keV. In the case of using the X-ray energy spectrum without using an additional filter, the amount of X-rays transmitted according to the thickness of the same material is different from the amount that decreases according to the thickness of the material. Similar results were obtained as the amount decreased with the material thickness. In other words, a similar result was obtained when the reduced dose was used with a mono energy. When an X-ray image is obtained by changing an X-ray energy spectrum using an additional filter, a more accurate result of transmission of X-rays may be obtained. In radiological examination, it was confirmed that the appropriate use of the additional filter has a great effect on improving the image quality.

• Journal of the Korean Society of Radiology
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• v.6 no.6
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• pp.483-487
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• 2012

In 1895, the discovered X-ray is used for not only in this field of medicine wide but also field. The detection of radiation after, people realized the risk of the radiation exposured recommended the principle about the protection of radiation by the part of the effort for lowering the radiation exposure. In this recommendation, all unnecessary radiation exposure have to be prevented by All doses include the protection of radiation, general idea of applicable two kinds of that it has to low maintain. Presently, in the General X-ray room of the clinical, the lead (Pb) was used for the shielding, However, because it had the problem of the lead poisoning which is fatal in the human body, the alternatives was showed. and Among them, the material that it is the tungsten was presented. in this research, the absorbed spectrum according to the thickness in the continuous X-ray energy of the tungsten which is not harmful to the human body through the Monte Carlo simulation, tried to compare with the absorbed spectrum of the lead (Pb). The tungsten confirmed that simulation presumption than result lead in the whole domain that absorbed probability was higher and it is considered that tungsten shows the absorbed efficiency higher than the lead in particularly, 70 keV ~ 90 keV and the tungsten is more useful to the X-ray energy cover of the high energy diagnostic area.

• Korean Journal of Optics and Photonics
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• v.9 no.4
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• pp.240-244
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• 1998

Cavity ring-down spectroscopy (CRDS) is a high-sensitive laser spectroscopic technique capable of measuring concentrations of trace gases. We have demonstrated a new design of the CRDS spectrometer with a continuous wave (CW) laser. The ring-dwon signal is produced through blocking the incident CW laser by scanning the cavity length fast toward off-resonance iwth PZT (piezoelectric transducer). We have also measured an absorption spectrum of acetylene overtone transitions near 570 nm at the pressure of 2700 Pa, and the minimum detectable absorption coefficient has been found to be about $3{\times}10^{-9}\cm^{-1}$.