• Journal of the Korean Geotechnical Society
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• v.33 no.4
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• pp.17-24
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• 2017

Shear wave velocity (or shear modulus) of rock filled zone of CFRD is very important factor in the evaluation of performance of CFRD under the load such as earthquake. A shear wave velocity profile can be determined by surface wave method but this profile has been uncertainty caused by spatial variation of material property in rock filled zone. This uncertainty in shear wave velocity profile could be evaluated by the reliability based analysis which uses a coefficient of variation of material property to consider uncertainty caused by spatial variation of material property. In this paper, the possible 600 shear wave velocity profiles in rock filled zone of CFRD were generated using the method based on harmonic wavelet transform and 8 shear wave velocity profiles by HWAW method in the field, and the coefficients of variation of shear wave velocity with depth were evaluated for the rock filled zone of CFRD in Korea.

• Journal of the Korea Concrete Institute
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• v.17 no.4 s.88
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• pp.535-542
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• 2005

Two series of experiments on the performance of beam-column joints in High-Strength Reinforced concrete frames were carried out. Main experimental parameters were : concrete strength, column axial load and amount of joint hoop reinforcement. Test result showed that the ultimate shear strength of exterior joints increased of column axial compressive force and the amount of the joint hoop reinforcements. Through the regression analysis on the 24data, the following equation is obtained $jv_u=(2.935{\times}10-3\;{\rho}jw{\cdot}fy\;+\;0.365){\sqrt{f_{ck}}}$

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2B
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• pp.345-351
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• 2010

It has been growing interests that convergence services of broadcasting and telecommunication services such as DMB 2.0 and Mobile IPTV etc. Unicast type is difficult to service broadcasting due to limits of capacity and poor receiving environments, WiBro supports broadcast service with MBS. MBS is transmission method that base stations belong to same the MBS zone transmit the all users who request broadcasting service. Terminals are received resources from all base station in the MBS zone and SINR can be improved because of macro diversity. If terminals are located at edge of the MBS zone, complement algorithm are needed beacause received SINR is very low. In this paper, MIMO STBC, Relay and FFR are introduced to improve the throughputs using high MCS. The basic simulation environment is assumed to be SISO. Transparent relay and FFR applicable on MBS are divided by SISO and MIMO STBC environment and evaluate the performance.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.703-706
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• 2005

본 논문에서는 스테레오 비전 알고리즘을 ARM9 프로세서를 사용하는 SoC의 IP 개념으로 구현하였다. 구현하고자 하는 스테레오 비전 시스템을 기능에 따라서 하드웨어와 소프트웨어 모듈로 나누어서 성능을 최대화할 수 있도록 설계하였다. SAD correlator는 한 쌍의 이미지에 많은 계산을 필요로 하기 때문에 성능을 우선시하여 하드웨어로 구성하였고, 소프트웨어는 프로세서를 초기화 시키고, 인터럽트 처리와 SAD correlator, TFT-LCD controller, 메모리 등의 하드웨어를 제어하는 역할을 하는 firmware로 구성을 하였다. 메모리에 기저장된 영상정보를 스테레오 비전 알고리즘을 이용한 결과를 외부 TFT-LCD 모듈에서 필요로 하는 포맷에 맞게 변환시켜서 depth map을 출력하는 시스템을 ARM922T 프로세서가 내장된 Altera Excalibur를 target으로 설계하여 테스트 보드에서 정상적으로 동작하는 것을 확인하였다.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1023-1024
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• 2007

외전형 모터는 내전형 모터에 비해 회전하는 회전자 부분이 외부에 존해해서 적은 토크에도 많은 출력을 얻을 수 있고 크기도 줄일 수 있기 때문에 송풍기용으로 많이 사용되고 있고, 점차적으로 프리미엄화 되어가고 있기 때문에 BLDC 모터를 채용하고 있는 추세이다. 본 논문에서는 기존에 양산되는 송풍기용 BLDC 모터를 대상으로 원가를 증가시키지 않고 출력 특성을 향상시키기 위한 최적 사양의 설계를 위해 다양한 변수들을 가지고 해석을 수행하였다. 또한 출력특성을 개선하기 위해서 코일의 선경, 턴 수와 적층 길이, 스큐 각도와의 상관 관계를 해석하여 외전형 BLDC 모터의 성능을 분석하여 보았고 모터의 전체적인 성능 향상과 원가 절감 등의 관점에서 해석을 수행하였다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.4
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• pp.370-376
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• 2005

For the purpose of investigating the effective removal of heating/cooling load from light-weighted building envelope, two air-conditioning systems, conventional parameter air-conditioning system and air-barrier system, are evaluated and compared by both experiment and simulation with six different cases during heating and cooling season. In addition, the characteristics of window-side building thermal load are assessed by varying supply air velocity in order to seek the optimal system operation condition. The results are as follows. 1) Air-barrier system is more effective to remove heating/cooling load at perimeter zone than conventional parameter air-conditioning system. Moreover, the better effectiveness appears during cooling season than during heating season. 2) The experiment during cooling season provides that indoor temperature of air-barrier system shows $1^{\circ}C$ less than that of the conventional system with similar outdoor air temperature profile, and indoor temperature distribution is more uniform throughout the experimented model space. It concludes that air-barrier system can achieve energy saving comparing to the conventional system. 3) The capturing efficiency of air-barrier system is 0.47 on heating season and 0.2 on cooling season with the same supply air volume. It results that the system performs effectively to remove building thermal load, moreover demonstrates high efficiency during cooling season. 4) The simulation results provide that capturing efficiency to evaluate the effective removal of building load from perimeter zone shows high value when supply air velocity is 1 m/s.

• Journal of Industrial Convergence
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• v.18 no.6
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• pp.1-7
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• 2020

In this study, we hypothesized that the needs for start-up support services may vary depending on the founder's psychological characteristics, such as self-efficacy or his attitude toward uncertainty. To verify this, a survey was conducted on the founders of 86 companies located in Business Incubators at Seoul and Daejeon and an empirical analysis was conducted based on the data. According to the analysis, the higher the self-efficacy of the founder, the more active he expressed his willingness to accept the start-up support service, which aims to provide start-up zones to busy areas outside the university. While the founder, who has experienced failure in the past, responded positively to attracting customers located outside the university. The results of this study supported the hypothesis and suggest that differentiated start-up support services should be designed by including not only characteristics at the level of start-up companies, such as industries and growth stages, but also the psychological characteristics of start-ups in important consideration.

• 보존과학연구
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• s.34
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• pp.102-108
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• 2013

The purpose of this investigation is to Dancheong documentary project of Tangible cultural in Jeollabukdo. The colored pigments of Nahanjeon Hall in Songkwangsa Temple analyzed and composition and repair period for each pigments were compared. The result are that blue color is Ultramarine blue($Na_6Al_6Si_6O_{24}S_4$), green color is Yangrok($Cu(C_2H_3O_2)_2{\cdot}3Cu(AsO_2)_3$), orange color is Jangdan($Pb_3O_4$), yellow color is Chrome yellow($PbCrO_4$). It is difficult to distinguishable from coloring period by analysis of pigments of Nahanjeon Hall.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.1
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• pp.46-56
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• 1994

The characteristics of flows, temperatures, concentrations of the boron are numerically studied when uniform axial magnetic fields are applied in the Czechralski crucible. The to governing factors to the flow regimes are buoyancy, thermocapillarity, centrifugal forces, magnetic forces, diffusion coefficient and segregation coefficient of the boron. Since the concentration of the boron is so low that buoyancy effects are negligible, it cannot affect the flow and temperature fields. From the fact that the flow fields are rotationally symmetric, two velocity components in the meridional plane and the circumferential velocity are calculated together with the temperature in the steady state. Based on the known velocity and temperature distributions the unsteady concentration distributions of the boron are calculated. As the strength of the magnetic is increased, the flow velocities are decreased. Circumferential velocities are large near the crucible side-wall and in the region below the rotating crystal. Steep temperatures gradient near the edge of the rotating crystal causes the Marangoni convection. It has been found out that the convection characteristics affects the unsteady transport phenomena of the boron.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.46 no.4
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• pp.70-76
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• 2009

We proposed the device to control a computer mouse with only head movements and eye blinks so that disabilities by car or other accidents can use a computer. The mouse position were estimated from a gyro-sensor which can measure head movements, and the mouse events such as click/double click were from opto sensors which can detect the eyes flicker, respectively. The sensor was mounted on the goggle in order not to disturb the visual field. There was no difference in movement speed between ours and a general mouse, but it required 3$\sim$4 more times in the result of the experiment to evaluate spatial movements and events detection of the proposed mouse because of the low accuracy. We could eliminate cumbersome work to periodically remove the accumulated error and intuitively control the mouse using non-linear relative point method with dead zones. Optical sensors are used in the event detection circuitry designed to remove the influence of the ambient light changes, therefore it was not affected in the change of external light source.