• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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• pp.58-63
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• 1998

B.Widrow established fundamental relations between the least-mean-square (LMS) algorithm and the digital Fourier transform［1］. By extending these relations, we proposed the short time spectra analysis system using the LMS algorithm［2]. In that paper, we used the normal LMS algorithm on the thought of dealing with only real analytical signal. This algorithm minimizes the real mean-square by recursively altering the complex weight vector at each sampling instant. But, the short time spectra analysis sometimes deals with the complex signal that is outputted from complex analog filter. So, in order to optimize and develop this methods, furthermore it is necessary to derive an algorithm for the complex analytical signal. In this paper, we first discuss the new adaptive system for the spectra analysis using the complex LMS algorithm and then derive convergence condition, time constant of coefficient adjustment and frequency resolution by extending the discussion. Finally, the effectiveness of the proposed method is experimentally demonstrated by applying it to the measurement of transfer performance on complex analog filter.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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• pp.528-531
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• 2004

For a simple one-dimensional ignition problem a mathematical model is described to investigate the difficulties in numerical simulations. Some computation results are obtained and comparison is made with analytical solution. Discussions are made on topics such as 1) coordinate transformation, 2) gas-phase and solid-phase analysis; (divergence form of the governing system, a finite-volume discretization, implicit time integration, upwind split flux, spatial accuracy improvement are described. Mass, reagent mass, and energy conservations are solved.), and 3) method to determine quantities on the burning surface (matching). Results obtained for small values of the non-dimensional pressure show a steady-combustion and good agreement with the analytical solution. Numerical instability appeared for larger values of the pressure, discussion on the cause of the problem is made. This effort is a part of a study of flame spread phenomena on solid propellant surface.

• 한국수학교육학회지시리즈A:수학교육
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• 제42권3호
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• pp.369-386
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• 2003

Problem-centered learning has many implications on teaching and learning mathematics. Students devise their solutions to solve problems and participate in the discussion with teacher and other students to share and justify their solution during the problem-centered learning. Therefore, we purposed to provide problem-centered loaming materials to be able to use in teaching and loaming the 7th mathematics curriculum in this study. First, we reviewed the 7th curriculum and its textbooks to know what and how students learn and suggested the problem-centered learning as a teaching method to perform the 7th curriculum. Next, we developed the problem-centered loaming materials for 6th grade in elementary school and taught students with these materials to amend errors. Finally, we developed evaluation criteria to evaluate students while they teamed mathematics in the problem-centered learning.

• 한국전문물리치료학회지
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• 제4권3호
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• pp.84-96
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• 1997

This paper reviews the developmental plan of industry in the industrial present condition of Korean Assistive Technology (Rehabilitation Engineering). The discussion includes the important role that go ahead the research of present condition about the enterprise of Assistive Technology (Rehabilitaton Engineering), reinforce the standard of equipment, the enterprise requesting the enlargement of facilities must lease a low late by the bank financing, give a necessary funds to a excellent minor enterprise, support a variety custom reduce method to buy a machine parts and machinery. The education master plan for rehabilitation engineer must be necessary the national medical engineer by establishing over one department at one big city and one province Further more research studies are required to realize on the developmental plan of Assistive Technology (Rehabilitation Engineering).

• 한국통신학회논문지
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• 제26권11A호
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• pp.1858-1863
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• 2001

SAR 데이터는 크기와 위상정보를 가지고 있으며, 위상정보를 이용하는 IFSAR 기법은 고 정밀 고도정보를 산출할 수 있는 매우 유용한 첨단기술이다. 본 논문에서는 SAR 운용시 IFSAR 기법을 효율적으로 활용할 수 있도록 하기 위하여 SAR 설계시 고찰해야할 필수적인 요구조건과 주요 고려사항을 제시하였다. 또한 핵심요소 중 하나인 최대 베이스라인에 대한 수식을 유도하였으며, E-SAR에 대한 시뮬레이션과 결과분석을 통하여 활용방안을 제안하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 Asia Navigation Conference
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• pp.213-219
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• 2006

Planning Environment Impact Assessment is regarded as one of the most important measures to achieve sustainable development in China. Conduct environment impact assessment for port planning was prescribed by Environment impact Assessment Law of the People's Republic of China. This Paper introduces the basic concept of Planning Environment Impact Assessment and Port Planning firstly, and then discusses the assessment indicators and assessment methods adopted in the Environment Impact Assessment for port planning. At last, the application of the indicators and methods are illustrated in case studies based on the practice on Port Planning's Environment Assessment in China.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권9호
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• pp.530-536
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• 2002

In this paper, a new torque ripple compensator is proposed. The proposed torque ripple compensator utilizes only speed information, so it can be easily applied to an existing motor drive system by including the algorithm. The stability analysis is discussed. From the discussion, the proper gain selection method, which makes the compensator stable and fast convergent, is also presented. The experimental results are presented and show the torque ripple reduction capability of the proposed scheme.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권6호
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• pp.362-366
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• 2002

A mathematical model has been developed for describing the oxygen concentration during the exponential growth of microorganisms, in a static solid substrate bed supported on a tray fermentor. The model equations comprise of one partial differential equation for mass transfer and an ordinary differential equation of growth. After nondimensionlisation, analytical solution tn the model has been obtained by the method of Laplace transforms. An expression for critical thickness of bed is deduced from the model equation. The significance of the model in the design of tray fermentors is discussed. The validity of the discussion is verified by taking an illustration from the literature.

• 한국시스템다이내믹스연구
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• 제12권4호
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• pp.63-92
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• 2011

The purpose of this paper is to investigate a possibility of applying multimethodological approach for solving a dilemma. The motivation of this attempt is that the two different approaches, the system dynamics and the theory of constraints, resemble each other in having mental models for describing the target system and using graphic tools for representing those mental models. After a brief discussion on the comparison of the two approaches, a combined method applying to the problem of dilemma is suggested. For an experimental example, the proposed approach is applied to the sales and finance conflict on an inventory issue. The study shows that the suggested approach is able to complement each other's drawbacks. Especially constructing a stock-and-flow model and implementing a computer simulation would be very useful for quantifying the system's behavior which is hardly tracked down when applying the theory of constraints alone.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.150-152
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• 2003

Laser scanned lidar data record 3D surface information in detail. Exploring valuable spatial information from lidar data is a prerequisite task for its applications, such as DEM generation and 3D building model reconstruction. However, the inherent spatial information is implicit in the abundant, densely and randomly distributed point cloud. This paper proposes a novel method to organize point cloud data, so that further analysis or feature extraction can proceed based on a well organized data model. The principle of the proposed algorithm is to segment point cloud into 3D planes. A split and merge segmentation based on the octree structure is developed for the implementation. Some practical airborne and ground lidar data are tested for demonstration and discussion. We expect this data organization could provide a stepping stone for extracting spatial information from lidar data.