• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.207-210
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• 2002

This paper is concerned with the experiments on the active vibration control of a plate with piezoceramic sensors and actuators. The natural frequencies of the composite plate featured by a piezo-film sensor and piezo-ceramic actuator are calculated by using the modal analysis method. Modal coordinates are introduced to obtain the state equations of the structural system. Six natural frequencies were considered in the modelling, because robust control theory which has inherent robustness to structured uncertainty is adopted to suppress the transients vibrations of a glass fiber reinforced(GFR) composite beam. A robust controller satisfying the nominal performance and robust performance is designed using robust theory based on the structured singular value. Simulations were carried out with the designed controller and effectiveness of the robust control strategy was verified by results.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1547-1550
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• 2005

ISB panel, inner structured of metal in two skin and bonded, has inner structures which have low relative density, stiffness and strength with low weight of make improvement for that purpose. A kind of Inner structures have various structure types. In this paper, we have studied the Forming Limit Diagram(FLD), thickness variation and stress strain to dimple structure of sheet by analysis of Dynaform and LS-Dyna.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1274-1277
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• 2004

The objective of this research work is to investigate into characteristics of bending stiffness and failure for the ISB ultra-lightweight panel with internally structured material. The expanded metal with a pyramid shape and woven metal are employed as an internally structured material. In order to investigate the characteristics, the specific stiffness and failure map are estimated using the results of three-points bending test. From the results of the experiment, the influence of design parameters of ISB panel on the specific stiffness and failure mode has been found. In addition, it has been shown that ISB panel with expanded metal is prefer to that with woven metal from the view point of optimal design for ISB panel.

• Proceedings of the Acoustical Society of Korea Conference
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• 1992.06a
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• pp.76-80
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• 1992

We consider the tapped-delay line (TDL) equalizer with the few calculation quantity and the simplity, the decision feedback equalizer (DFE) with the good property for interference, and lattice equalizer(LE) with high insensitivity to roundoff noise in mobile communication fading channel. The used adaptive algorithm is the LMS algorithm and RLS algorithm. In this paper, we have evaluated the performance of the TDL equalizer, the decision feedback equalizer, and lattice-structured equalizer, for the digital signal corrupted by the impulsive noise and the white gaussian noise under the fading channel environment. From the results of error performance analysis, it is confirmed that lattice-structured equalizer has better performance than DFE equalizer and TDL equalizer.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.06c
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• pp.75-78
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• 1998

이 논문에서는 대용량 연속음성 인식에서 인식 속도를 향상시키기 위한 방법들에 대해서 연구하였다. 음성인식에 있어서 많은 양의 계산을 요하는 부분은 관측 확률의 계산과 탐색에 필요한 계산이다. 탐색에 필요한 계산을 줄이기 위하여 빔 탐색법과 phoneme look-ahead기법을 통해 탐색 공간을 줄였으며, 관측 확률을 계산하는데 소요되는 시간을 줄이기 위하여 입력 특징 벡터와 이웃 관계에 있는 가우시안 성분들만 정확한 계산을 하는 VQ에 의한 계산량 감축 방법과 tree-structured pdf 방법을 구현하였다. 3천개의 어휘와 2천여개의 트라이폰 모델로 구성된 연속 음성인식 시스템에서 보통의 Viterbi 빔 탐색법을 적용한 경우에 실시간의 2.73배의 인식 속도로 93.39%의 단어 인식률을 얻을 수 있는데 phoneme look-ahead 기법과 tree-structured pdf 방법을 추가 적용함으로써 비슷한 인식 성능에서 1.55배의 인식 속도를 얻을 수 있었다.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.10
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• pp.1633-1638
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• 2016

Loop system arrangement in the primary distribution system has been increased for higher reliability of power supply to the customer. This paper presents a new fault calculation method for the loop structured unbalanced distribution feeders. Mathematical modeling method of the distribution system and superposition principal based fault calculation procedures are provided. In order to establish feasibility of the proposed method, various case studies have been performed using Matlab power system toolbox.

• Journal of Korean Medical classics
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• v.22 no.2
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• pp.305-313
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• 2009

With the recent increase of social demand of knowledge on traditional medicine, the construction of database is becoming a pressing matter. The reality is that while the social desire to adapt the high quality knowledge is growing fast, the field of Oriental Medicine has yet to organize its system. The number of Oriental Medical Doctors are limited, and there is no structured means of communication to expand the professional knowledge of these specialists to the public. Accordingly, an effective and structured knowledge system is in great need. In the process of building an Oriental Medicine database, prescription[方劑] and medicines[本草] are first in line. Consequently, we have taken the first step by organizing various methods to build the database containing information such as the formula, ingredients, composition, handling methods of herbal medicine written in traditional medical publications and herbal texts before the Song(宋) dynasty.

• Korean Management Science Review
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• v.20 no.2
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• pp.81-93
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• 2003

These days we come across many wicked problems whose solutions are beyond individuals intellectual ability. These problems can be resolved through collaborative group interaction. We developed an internet-based asynchronous group interaction support system, after looking into the collaborative problem solving process and the IBIS (Issue-Based Information System) argumentation model. It has the following characteristics ; 1) it is developed based on the modified IBIS model which is a model for group interaction to resolve wicked problems ; 2) it supports both processes of seeking and comparing solutions, while most similar systems do not have a feature to support the latter process ; 3) different structures can be defined dynamically according to the purpose of group interaction, so that it could be used for collaborative problem solving in a specific domain. To show the usability of the system, we carried out an experiment, whose result is shown at the end.

• Proceedings of the KIEE Conference
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• 2003.10a
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• pp.42-44
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• 2003

The paper presents the method and apparatus for conformal photoresist spray coating on the 3D structured substrate. The system consists of a high-temperature-rotational chuck, ultrasonic spray nozzle module, angle control module and nozzle moving module. The coating uniformity is acquired by controlling the moving speed of the ultrasonic spray nozzle across the substrate which is rotated constantly. To coat the photoresist conformally the spray angle of the nozzle and the temperature of the substrate are controlled during spray coating. The rotational chuck can be heated up by hot air or $N_2$. The photoresist (AZ1512) has been coated on the 3D structured wafer by spray coating system and the characteristics have been evaluated.

• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1830-1835
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• 2015

In this paper, we propose an algorithm for the automatic registration of two rigid parts using multiple 3D sensor systems on a robot. Four sets of structured laser stripe system consisted of a camera and a visible laser stripe is used for the acquisition of 3D information. Detailed procedures including extrinsic calibration among four 3D sensor systems and hand/eye calibration of 3D sensing system on robot arm are presented. We find a best pose using search-based pose estimation algorithm where cost function is proposed by reflecting geometric constraints between sensor systems and target objects. A pose with minimum gap and height difference is found by greedy search. Experimental result using demo system shows the robustness and feasibility of the proposed algorithm.