• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2004년도 정기총회 및 학술대회
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• pp.233-236
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• 2004

다양한 처리능력을 가진 단말기들은 복잡한 네트워크, 환경의 호환성을 제공하기 위해서, 전송 네트워크 채널이 허용하는 범위내로 부호화 된 비디오의 비트 율을 적응적으로 맞춰 주어야 한다 트랜스코더는 특정 비트율로 부호화되어 있는 비디오를 원하는 비트율의 다시 변환하기 위해서 복호화 만 후 다시 부호와의 과정을 거쳐야 하기 때문에 이에 따른 계산량의 증가와 더불어 전송시간에 문제가 발생한다. 이를 해결하기 위한 한 가지 방법으로 제안된 것이 프레임 건너뜀 기법 즉 시간적 해상도 변환 트랜스코딩이다. 비디오를 부호화하는 과정에서 계산량을 가장 많이 차지하는 움직임 추정과정의 계산량을 줄임으로써 트랜스코딩을 수행하는데 소모되는 시간과 노력을 크게 줄이고, 건너뛰지 않고 남아있는 프레임에 더 많은 비트를 할당하여 요구되는 화질을 유지할 수 있다. 본 논문에서는 움직임 벡터의 방향성을 고려한 움직임 벡터 재추정 기법과 정제 기법을 제안한다 제안된 기법인 E-FDVS(Efficient-Forward Dominant Vector Selection)는 움직임 벡터의 방향성을 고려하여 매크로블록과 움직임 벡터의 차이를 이용하여 움직임 벡터를 재추정한다. 그리고 제안한 기법인 DOS(Direction Oriented Search)를 사용하여 재추정 된 움직임 벡터의 방향으로 강한 움직임 벡터 정제를 함으로써 기존의 기법에 비해 우수한 화질을 제공한다.

• 한국측량학회지
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• 제21권2호
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• pp.173-180
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• 2003

세계측지계로의 전환으로 GPS는 측량분야에서 그 효용성이 크게 증가되고있는 현 시점에서, 기준점을 기준으로 이동점에 대한 상대적인 기선벡터를 구하는 기선해석프로그램은 대부분 외국 소프트웨어에 의존하고 있어 보다 폭넓은 활용에 걸림돌이 되고 있다. 본 논문에서는 LAMBDA 기법으로 미지정수를 해결하는 알고리즘을 정립하고, 객체지향언어인 Visual C＋＋ 6.0을 이용하여 Ll 반송파에 대한 기선해석 프로그램을 개발하였으며, 15km이하의 단기선에서 상용프로그램과 비교하여 4.9센티미터 이하의 차이를 확인하였다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2004년도 추계학술대회 및 정기총회
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• pp.463-466
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• 2004

This paper suggests the evaluation method of success factors of CRM implementation using AHP technique, and presents why firms implement CRM, how it could be successfully implemented, and what is the most important factor. For the purpose, this study applies the method to department stores' industry. AHP structure consists of three steps to determine CRM's key success factors. First of all, strengthening loyalty of customers, improvement of service quality, upgrade of intelligence system and advancement of management process are selected as superordinate object (i.e. CRM-implementation goal). The next project factor, technology/data factor and organizational factor were decided as success factor of CRM-implementation. Subordinate criteria of project factor consist of 11 criteria. The experimental results of this study show that department stores think advancement of management process and improvement of service quality as most important purposes for CRM implementation. The results also indicate that among the subordinate success factors, accuracy of customer information, conversion to customer-oriented business model, practical use of experienced consultant, and establishing IT infrastructure for CRM are evaluated as most important success factors for CRM implementation.

• Bulletin of the Korean Chemical Society
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• 제33권6호
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• pp.1989-1992
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• 2012

We present a low temperature (${\approx}70^{\circ}C$) method to prepare anatase, vertically aligned feather-like $TiO_2$ (VAFT) nanowire arrays $via$ reactive pulsed DC magnetron sputtering. The synthesis method is general, offering a promising strategy for preparing crystalline nanowire metal oxide films for applications including gas sensing, photocatalysis, and 3rd generation photovoltaics. As an example application, anatase nanowire films are grown on fluorine doped tin oxide coated glass substrates and used as the photoanode in dye sensitized solar cells (DSSCs). AM1.5G power conversion efficiencies for the solar cells made of 1 ${\mu}m$ thick VAFT have reached 0.42%, which compares favorably to solar cells made of the same thickness P25 $TiO_2$ (0.35%).

• 한국농촌건축학회논문집
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• 제10권1호
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• pp.1-9
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• 2008

The purpose of this study is to investigate and analyse the opinions of tourists and local commercial residents for remodelling of Youngwol Gossi-cave area so that to find the way how to activate it. Therefore this study has been focused on the opinions of tourists to visit it, local merchants to sell goods and foods and officers to take charge of the control office. The present conditions of Gossi-cave area are stagnated since the service level is low by the excessive competition among the local merchants. As a result, the inner troubles have arisen among the local merchants. Therefore firstly the sustainable and future-oriented remodelling development of Youngwol Gossi-Cave area is required. And then the basic remodelling plan of participant type to be centered with tourists and local residents as the central figures through local residents' ability strengthening must be established. Lastly the basic remodelling plan through the connection of surrounding tour resources and the resource increase of local amenities must be established. Also it is necessary for the conversion as a tour place of sojourn by supplying with various shows through connections among surrounding tour resources worthy of seeing and the creation of concept to provide the excitement through the education and experience in a basic remodelling plan direction of Youngwol Gossi-cave area.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.2001-2003
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• 2005

Various organic acid were used in order to prepare new metalorganic deposition solution for high quality $REBa_2Cu_3O_{7-{\delta}}$ (RE=Y, Eu, Gd) films. Prepared fluorine free MO precursor solution was coated on single crystal (001) $LaAlO_3$ (LAO) by dip coating method. Processing parameters such as oxygen partial pressure, water vapor, ramping rate and pyrolysis temperature etc havebeen controlled in order to make high $J_c$ films with a good epitaxial relationship with substrate. 0.5 micron-thick film was obtained by single coating and no crack appeared after calcination. Oxygen partial pressure was varied in the range of $100{\sim}1,000 ppm$ and conversion heat treatment was carried out at the temperature of $725{\sim}765^{\circ}C$. A critical transition temperature $(T_{c0})$ of 90K and a critical transport current density $(J_c)$ of $>0.5MA/cm^2$ (77K and self-field) were demonstrated for the YBCO film on (001) oriented LAO substrates with a thickness of 0.5 micron. $I_c$ was determined by utilizing a transport measurement. SEM and XRD investigations confirmed that films were grown epitaxially onto the LAO single crystal substrate. It is thought that fluorine free new MOD solutionis promising for high quality REBCO films.

• Journal of Power Electronics
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• 제7권2호
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• pp.159-173
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• 2007

In this paper, an intelligent sliding-mode position controller (ISMC) for achieving favorable decoupling control and high precision position tracking performance of permanent-magnet synchronous motor (PMSM) servo drives is proposed. The intelligent position controller consists of a sliding-mode position controller (SMC) in the position feed-back loop in addition to an on-line trained fuzzy-neural-network model-following controller (FNNMFC) in the feedforward loop. The intelligent position controller combines the merits of the SMC with robust characteristics and the FNNMFC with on-line learning ability for periodic command tracking of a PMSM servo drive. The theoretical analyses of the sliding-mode position controller are described with a second order switching surface (PID) which is insensitive to parameter uncertainties and external load disturbances. To realize high dynamic performance in disturbance rejection and tracking characteristics, an on-line trained FNNMFC is proposed. The connective weights and membership functions of the FNNMFC are trained on-line according to the model-following error between the outputs of the reference model and the PMSM servo drive system. The FNNMFC generates an adaptive control signal which is added to the SMC output to attain robust model-following characteristics under different operating conditions regardless of parameter uncertainties and load disturbances. A computer simulation is developed to demonstrate the effectiveness of the proposed intelligent sliding mode position controller. The results confirm that the proposed ISMC grants robust performance and precise response to the reference model regardless of load disturbances and PMSM parameter uncertainties.

• Journal of Information Processing Systems
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• 제1권1호
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• pp.79-85
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• 2005

In this paper, we dealt with substantial asset analysis methodology applied to two-dimensional asset classification and qualitative evaluation method according to the business process. Most of the existent risk analysis methodology and tools presented classification by asset type and physical evaluation by a quantitative method. We focused our research on qualitative evaluation with 2-dimensional asset classification. It converts from quantitative asset value with purchase cost, recovery and exchange cost, etc. to qualitative evaluation considering specific factors related to the business process. In the first phase, we classified the IT assets into tangible and intangible assets, including human and information data asset, and evaluated their value. Then, we converted the quantitative asset value to the qualitative asset value using a conversion standard table. In the second phase, we reclassified the assets using 2-dimensional classification factors reflecting the business process, and applied weight to the first evaluation results. This method is to consider the organization characteristics, IT asset structure scheme and business process. Therefore, we can evaluate the concrete and substantial asset value corresponding to the organization business process, even if they are the same asset type.

• 한국표면공학회지
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• 제52권5호
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• pp.258-264
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• 2019

Assembling heterostructures by combining dissimilar oxide semiconductors is a promising approach to enhance charge separation and transfer in photoelectrochemical (PEC) water splitting. In this work, the CuO nanorods array/$Cu_2O$ thin film bilayered heterostructure was successfully fabricated by a facile method that involved a direct electrodeposition of the $Cu_2O$ thin film onto the vertically oriented CuO nanorods array to serve as the photoelectrode for the PEC water oxidation. The resulting copper-oxide-based heterostructure photoelectrode exhibited an enhanced PEC performance compared to common copper-oxide-based photoelectrodes, indicating good charge separation and transfer efficiency due to the band structure realignment at the interface. The photocurrent density and the optimal photocurrent conversion efficiency obtained on the CuO nanorods/$Cu_2O$ thin film heterostructure were $0.59mA/cm^2$ and 1.10% at 1.06 V vs. RHE, respectively. These results provide a promising route to fabricating earth-abundant copper-oxide-based photoelectrode for visible-light-driven hydrogen generation using a facile, low-cost, and scalable approach of combining electrodeposition and hydrothermal synthesis.

• 융복합기술연구소 논문집
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• 제12권1호
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• pp.13-18
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• 2022

Polyacrylonitrile was synthesized through suspension polymerization and then sieved to obtain spherical beads with a size of 200~510 ㎛. PAN was copolymerized with 2 mol% MMA monomer which is known to promote cyclization and crosslinking of nitrile group. The resonance cyclization reaction of the nitrile group in the synthesized PAN beads was observed near 170℃ with thermal analysis and FT-IR. The reaction conversion of the nitrile group in spherical beads was 23% during heat treatment, which was lower than that of the well-oriented PAN fiber used as a precursor of carbon fiber. This is because the stereo-regularity of molecular chains in the form of a random coil (spherical bead) is much lower than that of PAN fiber. It was confirmed that the compressive strength of the spherical PAN bead was greatly improved through the resonance cyclization and shrinkage according to the heat treatment, and it was also observed that the pores in PAN beads were formed after the heat treatment.