• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.141-142
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• 2008

Single crystal $ZnIn_2S_4$ layers were grown on thoroughly etched semi-insulating GaAs(100) substrate at $450^{\circ}C$ with hot wall epitaxy (HWE) system by evaporating $ZnIn_2S_4$ source at $610^{\circ}C$. The temperature dependence of the energy band gap of the $ZnIn_2S_4$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g$(T) = 2.9514eV - ($7.24\times10^{-4}$ eV/K)$T^2$/(T + 489 K). After the as-grown $ZnIn_2S_4$ single crystal thin films was annealed in Zn-, S-, and In-atmospheres, the origin of point defects of $ZnIn_2S_4$ single crystal thin films has been investigated by the photoluminescence(PL) at 10 K. The native defects of $V_{Zn}$, $V_s$, $Zn_{int}$, and $S_{int}$, obtained by PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the S-atmosphere converted $ZnIn_2S_4$ single crystal thin films to an optical p-type. Also, we confirmed that In in $ZnIn_2S_4$/GaAs did not form the native defects because In in $ZnIn_2S_4$ single crystal thin films existed in the form of stable bonds.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.98-99
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• 2008

To obtain the single crystal thin films, $AgGaSe_2$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the hot wall epitaxy (HWE) system. The source and substrate temperatures were $630^{\circ}C$ and $420^{\circ}C$, respectively. The temperature dependence of the energy band gap of the $AgGaSe_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g$(T) 1.9501 eV - ($8.79\times10^{-4}$ eV/K)$T^2$/(T + 250 K). After the as-grown $AgGaSe_2$ single crystal thin films was annealed in Ag-, Se-, and Ga-atmospheres, the origin of point defects of $AgGaSe_2$ single crystal thin films has been investigated by the photoluminescence(PL) at 10K. The native defects of $V_{Ag}$, $V_{Se}$, $Ag_{int}$, and $Se_{int}$ obtained by PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the Ag-atmosphere converted $AgGaSe_2$ single crystal thin films to an optical p-type. Also, we confirmed that Ga in $AgGaSe_2$/GaAs did not form the native defects because Ga in $AgGaSe_2$ single crystal thin films existed in the form of stable bonds.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.3
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• pp.535-541
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• 2009

In this paper, we present the improvement on the performance of driving part for single-phase MJ81 switch point machine which has been developed for localization. The single-phase motor's specification and reliability for speed and safety improvement of conventional line was investigated in "Development project for Speed-up on Conventional Line" We systemized the test procedure fur single-phase motor by investigating the feasibility for localization and the specification of function and performance. Also, we developed appropriate technology and proved the durability of the single-phase driving motor by executing synthesis test over 200,000 times.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.6
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• pp.274-284
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• 2001

A stoichimetric mixture of evaporating materials for $AgInS_2$ single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films. $AgInS_2$mixed crystal was deposited on thorughly etched semi-insulating GaAs(100) substrate by the Hot wall Epitaxy (HWE) system. The source and substrate temperatures were $680^{\circ}C$ and $410^{\circ}C$, respectively. The crystalline structure of the single thin films was investigated by the photoluminescence and double crystal X-ray diffraction(DCXD). The carrier density and mobility of $AgInS_2$ single crystal the films measured from Hall effect by van der Pauw method are $9.35\times 10^{16}/\terxtm{cm}^3$ and $294\terxtm{cm}^2$/V.s at 293 K, respectively. From the optical absorption measurement the temperature dependence of the energy band gap on AgInS$_2$ single crystal thin film was found to be $E_g$(T)= 2.1365eV-($9.89\times 10^{-3}eV/T^2$/(2930+T). After the as-grown $AgInS_2$ single crystal thin films was annealed in $Ag^-S^-$ and In-atmospheres, the origin of point defects of AgInS$_2$ single crystal the films has been investigated by using the photoluminescence(PL) at 10K. The native defects of $V_{Ag},V_s, Ag_{int}$ and $S_{int}$ int/ obtained from PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the S-atmosphere converted $AgInS_2$ single crystal thin films to an optical p-type. Also, we confirmed that In in $AgInS_2$ /GaAs did not form the native defects because In is $AgInS_2$ single crystal thin films did exist in the form of stable bonds.

• Korean Journal of Acupuncture
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• v.29 no.1
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• pp.23-36
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• 2012

Objectives : This study was conducted to investigate effective treatment point selection method using oppressive pain in acupoints as elementary attempt for standard methodology of clinical acupuncture studies. Methods : Twenty seven subjects with hypertension or within prehypertension category - systolic and diastolic blood pressure (BP) over 120/80mmHg - were divided into two groups, oppressive pain point treatment group and oppressive painless point treatment group. In oppressive pain point treatment group, single point acupuncture (SPA) was conducted for 16 sessions during 8 weeks on most oppressive painful point among 6 selected acupuncture points used in previous trials and clinic. As a SPA intervention, 15 minutes with deqi sensation- elevating manipulation was conducted on the treatment acupoint. Same process was conducted in oppressive painless point treatment group on most oppressive painless point with subject blinding. Results : Significant reduction was observed in both systolic and diastolic BP after short time intervention (15.5/8.8 mmHg, 10.7/7.1 mmHg, P<0.05, respectively at 1 week) and maintained for 8 weeks intervention period in all groups (12.8/8.0 mmHg, 19.4/12.6 mmHg, P<0.05, respectively). No significant difference of BP change between oppressive pain point treatment group (N=10) and oppressive painless point treatment group (N=9) was observed during 8 weeks study period. Conclusions : SPA treatment as used in this pilot study was effective for lowering BP in mild hypertensive population, but oppressive pain in acupoint had no effect on treatment. This present result suggests the possibility of SPA for hypertension treatment regardless of oppressive pain.

• Journal of Korean Ophthalmic Optics Society
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• v.14 no.4
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• pp.45-51
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• 2009

Purpose: The purpose of this study is to compare and analyze the survey results of clinical performance and visual problem, and the survey were carried out before and after of VDT working for 4 hours by wearing functional lens designed for improving VDT syndrome and single-vision lens. Methods: We tested near & far visual acuity, change of spherical equivalent, near point of accommodation, near point of convergence, AC/A ratio, accommodative facility and survey of subjective symptoms to visual problem of before and after VDT working for 4 hours after wearing single-vision lens and functional lens subjected on 30 males and females in the age of 20 to 45. Results: When wearing functional lens comparing to single-vision lens, near visual acuity, near point of accommodation, near point of convergence, and accommodative facility are significantly improved. It is investigated that average scores of 10 items to visual problem after VDT working for 4 hours are 3.63${\pm}$0.75 at single-vision lens and 4.69 ${\pm}$ 0.83 at functional lens, and therefore functional lens is significantly improved. Conclusions: It is thought that functional lens is an excellent lens which helps to improve accommodative function and visual problem after VDT working for 4 hours than single-vision lens.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.2
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• pp.212-219
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• 2017

As an environmental pollution and global warming due to an excessive carbon emission are intensified, the importance of renewable energy is in rise today. TCP (Tidal Current Power), one of the renewable energy sources, generates electricity by converting kinetic energy of current into rotational energy of turbine. Also the TCP has a great advantages of predictability and reliability. Because the generating power is proportional to cubic of stream velocity, amplifying current speed by applying duct is highly effective to increase the generating power. SPM (Single Point Mooring) can be applied for the weather vane with various current direction and also augments generating power of the system. In addition, simple installation and retrieval could be a merit of SPM system. By combining duct and SPM, TCP system for relatively low-speed-current and shallow water region can be feasible and economical. In this study, single point moored duct-type TCP system was designed and the motion of submerged structure was investigated in both numerical and experimental method. DNV wadam V4.8-1 and OrcaFlex 10.0a were used for the frequency and time domain motion analysis of system respectively. Duct model scaled by 0.05 of Froude conformity ratio and CWC (Circulate Water Channel) are used for experiment.

• Water for future
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• v.29 no.2
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• pp.129-141
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• 1996

A procedure for computing total suspended sediment load is presented based on a single point-integrated sample, a power velocity distribution, and Laursen's sediment concentration distribution equation. The procedure was tested with field data from the Rio Grande River. Computed concentrations agreed well with depth-integrated measurements corrected for unmeasured load using nominal values of $\beta$, $\kappa$ and w. Even better agreement was obtained when site-specific data were used to define the x and z exponents of the velocity and concentration distributions. The difference between total suspended load computed using a single measurement and this procedure and conventional computations based on depthintegrated measurements is well within sampling error. There are major advantages in estimating total suspended load using a single time-integrated suspended-sediment point sample. Less field time is required; sampling costs are greatly reduced; and sampling can be more frequent and better timed to measure the changing sediment load. Single-point sampling makes automatic sampling procedures more feasible.

• The KIPS Transactions:PartA
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• v.8A no.4
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• pp.419-428
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• 2001

Advances in circuit and integration technology are continuously boosting the speed of processors. One of the main challenges presented by such developments is the effective use of powerful processors in shared memory multiprocessor system. We believe that the interconnection problem is not solved even for small scale shared memory multiprocessor, since the speed of shared buses is unlikely to keep up with the bandwidth requirements of new powerful processors. In the past few years, point-to-point unidirectional connection have emerged as a very promising interconnection technology. The single slotted ring is the simplest form point-to-point interconnection. The main limitation of the single slotted ring architecture is that latency of access increase linearly with the number of the processors in the ring. Because of this, we proposed the dual slotted ring as an alternative to single slotted ring for cache-based multiprocessor system. In this paper, we analyze the proposed dual slotted ring architecture using new snooping protocol and enforce simulation to compare it with single slotted ring.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.257-265
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• 2002

A stoichiometric mixture of evaporating materials for AgInS$_2$ single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, AgInS$_2$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy(HWE) system. The source and substrate temperatures were 680 $^{\circ}C$ and 410 $^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction(DCXD). The carrier density and mobility of AgInS$_2$ single crystal thin films measured from Hall effect by van der Pauw method are 9.35${\times}$10$\^$16/ cm$\^$-3/ and 294 $\textrm{cm}^2$/V$.$s at 293 K, respectively. From the optical absorption measurement, the temperature dependence of the energy band gap on AgInS$_2$ single crystal thin films was found to be E$\_$g/(T) : 2.1365 eV - (9.89 ${\times}$ 10$\^$-3/ eV) T$^2$/(2930 + T). After the as-grown AgInS$_2$ single crystal thin films was annealed in Ag-, S-, and In-atmospheres, the origin of point defects of AgInS$_2$ single crystal thin films has been investigated by using the photoluminescence(PL) at 10 K. The native defects of V$\_$AG/, V$\_$S/, Ag$\_$int/, and S$\_$int/ obtained from PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the S-atmosphere converted AgInS$_2$ single crystal thin films to an optical p-type. Also, we confirmed that In in AgInS$_2$/GaAs did not form the native defects because In in AgInS$_2$ single crystal thin films did exist in the form of stable bonds.