• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2009년도 하계학술발표대회 논문집
• /
• pp.730-735
• /
• 2009

The purpose of this study is to consider improvement performance to prevent condensation and draw the optimum insulation design method for building using simulation tool. In this study, the three corners, weak part in condensation, were conducted by three-dimensional steady state simulation. From the results, it is required to strengthen insulation design, and it is founded that existing insulation system typically applied to most Korean apartment buildings has serious insulation defect that insulation is disconnected by structural components at the joints of wall-slab and wall-wall in envelope. So, it is considerate to need a concrete technology improvement.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
• /
• pp.193.2-193.2
• /
• 2016

We evaluate the change in defects in the oxidized SiO2 grown on 4H-SiC (0001) by plasma assisted oxidation, by comparing with that of conventional thermal oxide. In order to investigate the changes in the electronic structure and electrical characteristics of the interfacial reaction between the thin SiO2 and SiC, x-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), DFT calculation and electrical measurements were carried out. We observed that the direct plasma oxide grown at the room temperature and rapid processing time (300 s) has enhanced electrical characteristics (frequency dispersion, hysteresis and interface trap density) than conventional thermal oxide and suppressed interfacial defect state. The decrease in defect state in conduction band edge and stress-induced leakage current (SILC) clearly indicate that plasma oxidation process improves SiO2 quality due to the reduced transition layer and energetically most stable interfacial state between SiO2/SiC controlled by the interstitial C.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
• /
• pp.420-420
• /
• 2013

We investigated oxygen plasma effect on defect states near the interface of AlGaN/GaN High Electron Mobility Transistor (HEMT) structure grown on a silicon substrate. After the plasma treatment, electrical properties were evaluated using a frequency dependant Capacitance-Voltage (C-V) and a temperature dependant C-V measurements, and a deep level transient spectroscopy (DLTS) method to study the change of defect densities. In the depth profile resulted from the temperature dependant C-V, a sudden decrease in the carrier concentration for two-dimensional electron gas (2DEG) nearby 250 K was observed. In C-V measurement, the interface states were improved in case of the oxygen-plasma treated samples, whereas the interface was degraded in case of the nitrogen-plasma treated sample. In the DLTS measurement, it was observed the two kinds of defects well known in AlGaN/GaN structure grown on sapphire substrate, which have the activation energies of 0.15 eV, 0.25 eV below the conduction band. We speculate that this defect state in AlGaN/GaN on the silicon substrate is caused from the decrease in 2DEG's carrier concentrations. We compared the various DLTS signals with filling pulse times to identify the characteristics of the newly found defect. In the filling pulse time range under the 80 us, the activation energies changed as the potential barrier model. On the other hand, in the filling pulse time range above the 80 us, the activation energies changed as the extended potential model. Therefore, we suggest that the found defect in the AlGaN/GaN/Si structure could be the extended defect related with AlGa/N/GaN interface states.

• Archives of Plastic Surgery
• /
• 제37권4호
• /
• pp.427-432
• /
• 2010

Purpose: The purpose of this study is to estimate muscle defect by ultrasonography in the patients with secondary deformities of the lip. We investigated the association between the muscle defect in the repaired cleft lip and the philtral appearance not only at resting state but also maximal puckering. Methods: From December 2006 to November 2007, 52 children were evaluated after primary or secondary cheiloplasty. Digital photographs were taken both from the front and both three quarter views in repose and at maximal pucker. Video clips were also taken in repose and at maximal pucker. A panel of four, scored the philtral ridge and dimple seen on these photographs and videos by using two visual analog scales. Eminence of the philtral ridge was scored by a 5 point grading scale, from "conspicuous groove" to "normal philtral ridge" and the philtral dimple was scored by 3 point grading scale, from "no dimple" to "prominent dimple". Ultrasound images of the upper lip were made using a linear array transducer at the resting position of the lip and evaluated by a single radiologist. Results: The philtral ridge eminence scored $2.79{\pm}0.54$ and $1.40{\pm}0.53$ at resting and maximal pucker, correlating with "flat" and "conspicous groove". The philtral dimpling scored $1.44{\pm}0.53$ and $2.27{\pm}0.66$ at resting and maximal pucker, correlating with "no dimple" and "slight dimple". Ultrasound imaging showed the average muscle dehiscence to be $3.78{\pm}2.14$ mm at resting position. Correlation between the muscle defect in ultrasound imaging and philtral ridge eminence at rest was statistically significant (p<0.050), but was not significant (p=0.756) at maximal pucker using Spearman's rank correlation. Correlation between the muscle defect in ultrasound imaging and philtral dimpling was not statistically significant both at rest (p=0.920) and at maximal pucker (p=0.815) using Spearman's rank correlation. Conclusion: Quantitative assessment of the muscle defect using ultrasonography correlates with the static philtral appearance, but does not correlate with the dynamic appearance. Also, the size of the muscle defect does not show any correlation with the philtral dimpling. Our findings reveal that ultrasound imaging partially reflect static appearance of philtrum but cannot reflect dynamic appearance and suggest the need for further research to evaluate dynamic appearance.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
• /
• pp.314-314
• /
• 2012

The dilute magnetic semiconductors (DMS) have been developed to multi-functional electro-magnetic devices. Specially, the Si based DMS formed by ion implantation have strong advantages to improve magnetic properties because of the controllable effects of carrier concentration on ferromagnetism. In this study, we investigated the deep level states of Fe- and Co-ions implanted Si wafer during rapid thermal annealing (RTA) process. The p-type Si (100) wafers with hole concentration of $1{\times}10^{16}cm^{-3}$ were uniformly implanted by Fe and Co ions at a dose of $1{\times}10^{16}cm^{-2}$ with an energy of 60 keV. After RTA process at temperature ranges of $500{\sim}900^{\circ}C$ for 5 min in nitrogen ambient, the Au electrodes with thickness of 100 nm were deposited to fabricate a Schottky contact by thermal evaporator. The surface morphology, the crystal structure, and the defect state for Fe- and Co- ion implanted p-type Si wafers were investigated by an atomic force microscopy, a x-ray diffraction, and a deep level transient spectroscopy, respectively. Finally, we will discuss the physical relationship between the electrical properties and the variation of defect states for Fe- and Co-ions implanted Si wafer after RTA.

• Archives of Plastic Surgery
• /
• 제37권4호
• /
• pp.421-426
• /
• 2010

Purpose: Patients with serious burns are prone to chondritis due to lack of soft tissue in the auricle, which can cause severe defects in the auricular morphology. In addition, skin damage occurs frequently in the vicinity of post-burn wounds, presenting difficulties in reconstruction surgery. An auricular reconstruction has functional and cosmetic significance. The aim of this study is to develop appropriate reconstruction methods for auricular defects. Methods: Thirty seven patients, who were treated for auricular defects from 2005 to 2009, were enrolled in this study. A local flap, multiple regional flaps and cartilage framework with or without a temporal fascial flap were applied in reconstruction surgery according to the location of the auricular defect. Results: The age of the subjects ranged from 11 to 56. Some subjects had defects that cover more than half of the helical rim with most exhibiting post-burn scars in the vicinity, for whom a multiple regional flap was used. A single use of a tubed flap was sufficient for subjects with defects that covered less than half of the helical rim. A regional flap was also used for reconstruction in subjects with defects covering both the helical rim and antehelix. Conclusion: Achieving satisfactory results from the skin flaps and skin grafts for post-burn auricular defects in both functional and cosmetic aspects is a difficult task. Therefore, selecting an appropriate surgical method through proper diagnosis of the auricular defect and the state of the available skin in the vicinity is essential.

• Journal of Electrical Engineering and Technology
• /
• 제11권2호
• /
• pp.436-444
• /
• 2016

Oil-paper insulation of valve-side windings in converter transformers withstand electrical stresses combining with AC, DC and strong harmonic components. This paper presents the physical mechanisms and experimental researches on partial discharge (PD) of oil-paper insulation at pulsating DC voltage. Theoretical analysis showed that the phase-resolved distributions of PDs generated from different insulated models varied as the increase of the applied voltages following a certain rule. Four artificial insulation defect models were designed to generate PD signals at pulsating DC voltages. Theoretical statements and experimental results show that the PD pulses first appear at the maximum value of the applied pulsating DC voltage, and the resolved PD phase distribution became wider as the applied voltage increased. The PD phase-resolved distributions generated from the different discharge models are also different in the phase-resolved distributions and development progress. It implies that the theoretical analysis is suitable for interpretation of PD at pulsating DC voltage.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제13권4호
• /
• pp.402-409
• /
• 2013

An innovative application of voltage-contrast (VC) inspection allowed inline detection of NMOS leakage in dense SRAM cells is presented. Cell sizes of SRAM are continual to do the shrinkage with bit density promotion as semiconductor technology advanced, but the resulting challenges include not only development of smaller-scale devices, but also intra-devices isolation. The NMOS leakage caused by the underneath n+/P-well shorted to the adjacent PMOS/N-well was inspected by the proposed electron-beam (e-beam) scan in which VC images were compared during the in-line process step of post contact tungsten (W) CMP (Chemical Mechanical Planarization) instead of end-of-line electrical test, which has a long response time. A series of experiments based on the mechanism for improving the intra-well isolation was performed and verified by the inline VC inspection. An optimal process-integration condition involved to the tradeoff between the implant dosage and photo CD was carried out.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2006년도 하계종합학술대회
• /
• pp.881-882
• /
• 2006

According as society looks graying trend gradually, more shaped system that can achieve measuring health-state of old people more harmoniously construction required in field of old people's welfare and medical treatment. Health-state is measured by two methods of contact and non-contact. The first, for example measurement of blood pressure or electrocardiogram, requires that measuring equipments are attached on human body but the second, for example X-Ray or MRI, is not. But both of methods are have some of defect, for example attaching equipments, needing of the special equipments or the necessary time, etc. Therefore desirable method of monitoring system must have minimum interrupt about daily life. This study suggest the system that can monitor the user, especially old people's outward aging and health-state by use the PAN TILTER and CCD camera.

• 전자통신동향분석
• /
• 제34권5호
• /
• pp.99-112
• /
• 2019

A quantum light source is an essential element for quantum information technology, including quantum communication, quantum sensor, and quantum computer. Quantum light sources including photon number state, entangled state, and squeezed state can be divided into two types according to the generation mechanism, namely single emitter and non-linear based systems. The single emitter platform contains atom/ion trap, solid-state defect/color center, two-dimensional material, and semiconductor quantum dot, which can emit deterministic photons. The non-linear based platform contains spontaneous parametric down-conversion and spontaneous four-wave mixing, which can emit probabilistic photon pairs. For each platform, we give an overview of the recent research trends of the generation, manipulation, and integration of single photon and entangled photon sources. The characteristics of quantum light sources are investigated for each platform. In addition, we briefly introduce quantum sensing, quantum communication, and quantum computing applications based on quantum light sources. We discuss the challenges and prospects of quantum light sources for quantum information technology.