• Journal of computational fluids engineering
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• v.3 no.2
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• pp.65-72
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• 1998

From the Boltzmann equation with BGK approximation, a gas-kinetic BGK scheme is developed and methods for its efficient calculation, using the convergence acceleration techniques, are presented in a framework of an implicit time integration. The characteristics of the original gas-kinetic BGK scheme are improved in order for the accurate calculation of viscous and heat convection problems by considering Osher's linear subpath solutions and Prandtl number correction. Present scheme applied to various numerical tests reveals a high level of accuracy and robustness and shows advantages over flux vector splittings and Riemann solver approaches from Euler equations.

• Proceedings of the KIEE Conference
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• 2003.04a
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• pp.200-207
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• 2003

Today we have excellent motor drive system using high frequency carrier PWM control voltage source inverter with vector control strategy. In the other hand, we have met serious problems caused by high frequency switching. PWM Cyclo-converter called Matrix converter is expected as the new strategy possible to improve these problems and add some more convenient features suitable for new drive system with system integration. In this paper, we will introduce the background of this development and features of this converter from our research, additionally introduce remarkable active promotions for this converter as a survey.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.883-885
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• 2005

지지 벡터 기계(Support Vector Machine: SVM)를 이용한 다중부류 분류기법이 최근 활발히 연구되고 있다. SVM은 이진분류기이기 때문에 다중부류 분류를 위해서 다수의 분류기를 구성하고 이들을 효과적으로 결합하는 방법이 필요하다. 본 논문에서는 기존의 정적인 다중분류기 결합 방법과는 달리 포섭구조의 분류모델을 확률에 따라 동적으로 구성하는 방법을 제안한다. 확률적 분류기인 나이브 베이즈 분류기(NB)를 이용하여 입력된 샘플의 각 클래스에 대한 확률을 계산하고, OVA (One-Vs-All) 전략으로 구축된 다중의 SVM을 획득된 확률에 따라 포섭구조로 구성한다. 제안하는 방법은 OVA SVM에서 발생하는 중의적인 상황을 효과적으로 처리하여 고성능의 분류를 수행한다. 본 논문에서는 지문분류 문제에서 대표적인 NIST-4 지문 데이터베이스를 대상으로 제안하는 방법을 적용하여 $1.8\%$의 거부율에서 $90.8\%$의 분류율을 획득하였으며, 기존의 결합 방법인 다수결 투표(Majority vote), 승자독식(Winner-takes-all), 행동지식공간 (Behavior knowledge space), 결정템플릿(Decision template) 등보다 높은 성능을 확인하였다.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.8
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• pp.798-804
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• 2006

To overcome the limited relative uncertainty and work range of the existing planar stage and the bulk structure of the contact-less motor for rotation, the novel operating principle to realize the precise rotation is suggested. It uses the two-axial vector forces, normal force and thrust force, of three-induction type of axial motors located $120^{\circ}$ apart, resulting in the contact-free rotation of the mover. Firstly in this paper, the magnetic forces across the air gap are modeled and simulated under the various conditions. It clarifies the feasible range of the derived solution. And the algorithm compensating the strong cross couple between the forces and the control inputs; generally AC magnitude and slip frequency, is given to realize the independent control of six axes. Finally, for the successfully implemented system, the round test and the micro step test results are given.

• Journal of Information Technology Applications and Management
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• v.13 no.4
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• pp.121-140
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• 2006

UDDI (Universal Discovery Description and Integration) Registry is used for Web Services registration and search. UDDI offers the search result to the keyword-based query. UDDI supports WSDL registration but it does not supports WSDL search. So it is required that contents based search and ranking using name and description in UDDI registration information and WSDL. This paper proposes a retrieval engine considering contents of services registered in the UDDI and WSDL. It uses Vector Space Model for similarity comparison between contents of those. UDDI registry information hierarchy and WSDL hierarchy are considered during searching process. This engine suppports two discovery methods. One is Keyword-based search and the other is template-based search supporting ranking for user's query. Template-based search offers how service interfaces correspond to the query for WSDL documents. Proposed retrieval engine can offer search result more accurately than one which UDDI offers and it can retrieve WSDL which is registered in UDDI in detail.

• Korean Institute of Interior Design Journal
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• no.29
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• pp.257-264
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• 2001

To propose the construction of architectural interior design and communication using graphic, web3D, it was studied the kind and character of various representation methods that can be embodied in an architectural interior design on the web, and looks into whether these ways can be adapted to an architectural interior design process. Especially, the use of the current techniques on graphic and CAD data give the most suitable effect by using the integrated data such as vector animation, an interaction of object VR(Virtual Reality), a high quality of panorama VR, and data treatment and its interaction of drawing of cad data. As a result, the single data format shows not only one image representation but also a stream of continuous operation through a change into another format. But this desired study expects that another next studies will go on interaction and integration of digital format with increase of transmission speed expected in the future, and a digital model and its practical methods.

• Bulletin of the Korean Chemical Society
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• v.4 no.1
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• pp.17-25
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• 1983

The hyperfine integrals for 4d orbitals have been evaluated adopting a general method which is applicable to a general vector, R, pointing arbitrary direction in space. The operator and the spherical harmonic part of 4d orbitals are expressed in terms of R and r$_{N}$ and the exponential part, r$^{2}$exp(-2${\beta}$r), of 4d orbitals is also translated as a function of R and r$_{N}$ and then integration is performed. The radial integrals for 4d orbitals are tabulated in analytical forms. The hyperfine integrals for 4d orbitals are also represented in analytical forms, using the specific formulas of radial series which we found.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.68 no.1
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• pp.189-198
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• 2019

In recent years, visual-inertial odometry(VIO) algorithms have been extensively studied for the indoor/urban environments because it is more robust to dynamic scenes and environment changes. In this paper, we propose loosely coupled(LC) VIO algorithm that utilizes the velocity vectors from both visual odometry(VO) and inertial measurement unit(IMU) as a filter measurement of Extended Kalman filter. Our approach improves the estimation performance of a filter without adding extra sensors while maintaining simple integration framework, which treats VO as a black box. For the VO algorithm, we employed a fundamental part of the ORB-SLAM, which uses ORB features. We performed an outdoor experiment using an RGB-D camera to evaluate the accuracy of the presented algorithm. Also, we evaluated our algorithm with the public dataset to compare with other visual navigation systems.

• Journal of Plant Biotechnology
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• v.37 no.1
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• pp.102-109
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• 2010

Fructan has been found to accumulate in various tissues during periods when light levels increased carbon fixation where low temperatures reduced growth rates while photosynthesis continued. In this study, we have cloned 1-sucrose:sucrose fructosyl transferase(1-sst) and 1-fructan: fructan fructosyl transferase (1-fft, a key enzyme for the synthesis of fuctan) from Jerusalem Artichoke (Helianthus tuberosus L.). The recombinant vector with 1-sst and 1-fft has been constructed under the control of 35S promoter of KJGV-B2 vector and transgenic plants obtained by Agrobacterium tumefaciens LBA4404. PCR analysis carried out on the putative transgenic plants for amplification of the coding region of specific gene (1-sst, 1-fft), and HPT genes. Transgenic lines carrying of 1-sst and 1-fft were confirmed for integration into the rice genome using Southern blot hybridization and RT-PCR. The transgenic plants in $T_2$ generation were selected and expression pattern analysis revealed that 1-sst and 1-fft were stable. This analysis confirmed the presence of low-molecular-weight fructan in the seedling of the transgenic rices. Therefore, cold tolerance and carbohydrate metabolism will be possible to develop resistant plants using the transgenic rice.

• Korean Journal of Remote Sensing
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• v.34 no.5
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• pp.739-747
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• 2018

Integration analysis of multi-sensor satellite images is becoming increasingly important. The first step in integration analysis is image registration between multi-sensor. SIFT (Scale Invariant Feature Transform) is a representative image registration method. However, optical image and SAR (Synthetic Aperture Radar) images are different from sensor attitude and radiation characteristics during acquisition, making it difficult to apply the conventional method, such as SIFT, because the radiometric characteristics between images are nonlinear. To overcome this limitation, we proposed a modified method that combines the SAR-SIFT method and shape descriptor vector DLSS(Dense Local Self-Similarity). We conducted an experiment using two pairs of Cosmo-SkyMed and KOMPSAT-2 images collected over Daejeon, Korea, an area with a high density of buildings. The proposed method extracted the correct matching points when compared to conventional methods, such as SIFT and SAR-SIFT. The method also gave quantitatively reasonable results for RMSE of 1.66m and 2.45m over the two pairs of images.