• Proceedings of the Computational Structural Engineering Institute Conference
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• 1991.10a
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• pp.96-101
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• 1991

프리스트레스트 콘크리트 교량은 콘크리트와 PS 강재의 역학적 장점들을 십분 활용하여 경제적인 단면 구성이 가능한 반면, 서로 다른 두 재료의 복합적인 특성들 즉, 콘크리트의 크리이프 (creep), 건조수축 (shrinkage)과 PS 강재의 이완 (relaxation) 등과 같이 시간에 따라 변화하는 인자들로 인하여 복잡한 구조적 거동을 보여 해석상 어려움이 따른다. 이와같은 복합거동은 시공순서와 시공방법에 의해 시공중의 구조계와 지지조건 등이 변화하는 경우에는 더욱 복잡한 양상을 띄게 된다. 뿐만 아니라 박스 거더와 같은 박벽요소에서는 일반적인 보요소(beam element)로는 나타낼 수 없는 ？(warping)을 무시할 수 없으므로 ？ 자유도를 구현할 수 있는 특수한 기능의 구조해석용 프로그램의 개발이 절실히 요망된다. 그리고 시공단계별로 출력되는 많은 양의 수치결과들을 설계와 시공실무자에 지향된 형태로 조합, 변형시켜 그래픽 화면상에 나타내는 후처리 프로그램(Post-processor) 기능도 구조해석용 프로그램의 개발 못지않게 중요하다. 본 연구의 목적은 삼성종합건설과 서울대 토목공학과가 공동으로 ？(warping) 자유도를 포함한 7개의 자유도를 갖는 3차원 보요소를 사용하여 PS 콘크리트의 재료적 특성인 크리이프와 건조수축, 그리고 강재의 이완(relaxation)을 포함한 프리스트레싱력의 손실을 고려할 수 있고 시공 단계별 구조계의 변화 및 지지조건들의 다양한 변화를 효율적으로 모사할 수 있는 프로그램의 개발에 있다.

• Journal of Oral Medicine and Pain
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• v.14 no.1
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• pp.67-80
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• 1989

The author studied the changes of muscle activity with Bioelectric processor Model EM2(Myotronics Corp., USA) before and after occlusal stabilization splint therapy. For this study, 15 temporomandibular disorders patients and 15 students without any temporomandibular disorders symptoms were selected, for experimental group and control group, respectively. Experimental group were treated with occlusal stabilization splint and checked about electromyographic activity before and after therapy. Electromyographic levels were measured in both groups at the following mandibular position, i.e., physiologic rest, tapping, light biting, hard open without pain, open with pain, right excursion and ipsilateral biting, left excursion and ipsilateral biting, protrusion, protrusive biting, edge biting and physiologic rest after movement. The obtained results were as follows : 1. In experimental group, post-treatment mean values of muscle activity were lower than pretreatment values. 2. In general, the pre-treatment mean values of muscle activity in experimental group were higher than those of control group. 3. In experimental group, no statistically significant difference appeared between affected and unaffected side. 4. The mean value of muscle activity in physiologic rest position after each movement check was lower than that before each movement check.

• Water for future
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• v.28 no.5
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• pp.163-174
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• 1995

A diffusion hydrodynamic model named "DFLOW-2" for the floodwave analysis from levee-break in protected lowland has been developed. The model has been applied to Ilsan levee-break, which occurred on September 12-13, 1990 in the downstream of the Han River. An unsteady flow analysis has been made in the reach from Indokyo to Junryu. Overflow through broken levee has been treated as internal boundary condition in the channel. A post-processor has been also developed to demonstrate the simulation results. The velocity distributions and inundated depths have been presented. The computed results have good agreements with observed data in terms of inundation depth, flood arrival time and flooded areas.ded areas.

• Korean Journal of Cognitive Science
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• v.22 no.3
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• pp.327-345
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• 2011

In this paper, a new approach to Korean POS (Part-of-Speech) tagging is proposed. In previous works, a Korean POS tagger was regarded as a post-processor of a morphological analyzer, and as such a tagger was used to determine the most likely morpheme/POS sequence from morphological analysis. In the proposed approach, however, the POS tagger is supposed to generate the most likely morpheme and POS pair sequence directly from the given sentences. 398,632 eojeol POS-tagged corpus and 33,467 eojeol test data are used for training and evaluation, respectively. The proposed approach shows 96.31% of POS tagging accuracy.

• Journal of the Korea Society of Computer and Information
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• v.17 no.11
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• pp.1-10
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• 2012

In this paper, the extension of the addressing mode in the 16-bit Thumb instruction set architecture is proposed to improve the performance of 16-bit Thumb code. The key idea of the proposed approach is the introduction of new addressing modes for more frequent instructions by using the saved bits from the reduction of the register fields in less frequently used instructions. The proposed approach adopts efficient addressing modes from the 32-bit ARM architecture, which is the superset of the 16-bit Thumb architecture. To speed up access to a data list, scaled register offset addressing mode and post-indexed addressing mode are introduced for load and store instructions. Experiments show that the proposed approach improves performance by an average of 8.5% when compared to the conventional approach.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.361-363
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• 2005

본 논문에서는 MPEG-4 Version2 Audio 표준에 근거하여 낮은 연산부담을 갖는 독자적인 엘고리즘을 적용한 MPEG-4 BSAC Audio 디코더를 개발하였다. 개발된 BSAC 디코더는 32bit RISC 구조를 갖는 Intel Xscale Processor 기반 시스템에 최적화하여 구현 및 평가를 수행하였다. 수행속도 증가 및 연산 정밀도 향상을 위해 각 기능 블록별 기능 및 구현 원리 연구와 32 bit 연산 구조를 파악하여, 이를 고정소수점 연산 구조로 구현함으로써 성능을 향상시켰다. 유한비트에 따른 오차 영향을 최소화하기 위해 데이터의 표현 범위에 대한 연구를 통해 근사한 오차를 최소화 하여 연산 정밀도를 향상 시키고자 하였다. 비선형 양자화기 및 filter bank 등 상대적으로 높은 연산 부담을 갖는 기능 블록은 Table look-up, 보간법, 지수연산 제거, pre/post scrambling 기법 등을 적용하여 최적화 하였다. 최종적으로 개발된 BSAC 디코더는 32 bit 연산 구조의 X-scale 프로세서를 탑재한 Development Board와 WindowsCE OS로 구성된 타겟 system에 이식하여 performance 평가하였으며, 높은 연산 정밀도 및 다른 수행속도를 확인할 수 있었다. 주관적인 청각 평가에서도 MPEG-4 reference 디코더와의 음원의 차이가 거의 없음을 확인하였다.

• The Journal of the Acoustical Society of Korea
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• v.16 no.3E
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• pp.50-55
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• 1997

Based on the anthropometric data of Korea male adults, a head and torso simulator(HATS) is constructed to measure its head related transfer functions (HRTFs) which can be used for three dimensional (3-D) sound localization. The HRTFs binaural impulse responses, are measured in an anechoic chamber using a burst maximum length sequence (MLS) signal of 65,535 samples and 32,768 samples acquisition at the sampling rate of 75.47kHz. Also measured are the impulse responses of a driving loudspeaker and some headphones for sound reproduction to get the exact HRTF of the HATS-alone. Through a post-processing procedure, the impulse-version HRTFs at the sampling frequency of 44.1 kHz, which have filter lengths of 512 points, are finally obtained. As an application of the measured HRTFs, a 3-D sound processor for headphone reproduction has been developed. The signal intervals to be processed can be selected and each interval is manipulated to have its diretionality and distance information by using corresponding HRTF and energy control.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.6
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• pp.389-397
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• 2015

Recently, wave propagation imaging based on laser scanning-generated elastic waves has been intensively used for nondestructive inspection. However, the proficiency of the conventional software based system reduces when the scan area is large since the processing time increases significantly due to unavoidable processor multitasking, where computing resources are shared with multiple processes. Hence, the field programmable gate array (FPGA) was introduced for a wave propagation imaging method in order to obtain extreme processing time reduction. An FPGA board was used for the design, implementing post-processing ultrasonic wave propagation imaging (UWPI). The results were compared with the conventional system and considerable improvement was observed, with at least 78% (scanning of $100{\times}100mm^2$ with 0.5 mm interval) to 87.5% (scanning of $200{\times}200mm^2$ with 0.5 mm interval) less processing time, strengthening the claim for the research. This new concept to implement FPGA technology into the UPI system will act as a break-through technology for full-scale automatic inspection.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.04b
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• pp.30-33
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• 2004

Shallow p+-n junctions were formed by low-energy ion implantation and dual-step annealing processes The dopant implantation was performed into the crystalline substrates using $BF_2$ ions. The annealing was performed with a rapid thermal processor and a furnace. FA+RTA annealing sequence exhibited better junction characteristics than RTA+FA thermal cycle from the viewpoint of junction depth. A new simulator is designed to model boron diffusion in silicon, which is especially useful for analyzing the annealing process subsequent to ion implantation. The model which is used in this simulator takes into account nonequilibrium diffusion, reactions of point defects, and defect-dopant pairs considering their charge states, and the dopant inactivation by introducing a boron clustering reaction. Using a resonable parameter values, the simulator covers not only the equilibrium diffusion conditions but also the nonequilibrium post-implantation diffusion. Using initial conditions and boundary conditions, coupled diffusion equation is solved successfully. The simulator reproduced experimental data successfully.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.5
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• pp.871-876
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• 2006

In this thesis, to accurately measure 3D face information using the spatial encoding patterns, the new algorithm to segment the pattern images from initial face pattern image is proposed. If the obtained images is non-homogeneous texture and ambiguous boundary pattern, the pattern segmentation is very difficult. Furthermore. the non-encoded areas by accumulated error are occurred. In this thesis, the FCM(fuzzy c-means) clustering method is proposed to enhance the robust encoding and segmentation rate under non-homogeneous texture and ambiguous boundary pattern. The initial parameters for experiment such as clustering class number, maximum repetition number, and error tolerance are set with 2, 100, 0.0001 respectively. The proposed pattern segmentation method increased 8-20% segmentation rate with conventional binary segmentation methods.