• Title/Summary/Keyword: 이영식

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Design and Fabrication of Triple-coupler Ring Resonator Filter (삼중 결합 링 공진기 필터의 설계 및 제작)

  • Lee, Young-Sik;Chung, Young-Chul
    • Korean Journal of Optics and Photonics
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    • v.22 no.1
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    • pp.40-45
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    • 2011
  • Design and fabrication of a TCRR (Triple-coupler Ring Resonator) filter which can provide a doubled FSR (Free Spectral Range) compared with a conventional DCRR (Double-coupler Ring Resonator) filter, are discussed. Through the use of a polymer material with a good thermo-optic property and with high contrast between core and cladding polymer, a compact TCRR filter composed of straight and curved buried waveguides of small radius is designed and fabricated. The transmission characteristics from the through and drop ports are measured using a tunable laser and a fiber array block, and the FSR is observed to be 4.4 nm, about twice that of DCRR filter, and almost the same as that obtained from the analysis using a transfer matrix method.

Growth of the Indigenous Red-tide Phytoplankton Assemblage with the Addition of Limiting Nutrients (제한영양염 첨가에 따른 자생 적조 식물플랑크톤의 증식)

  • Lee, Young-Sik
    • Journal of Environmental Science International
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    • v.15 no.10
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    • pp.961-966
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    • 2006
  • An algal assay procedure using an indigenous phytoplankton assemblage was tested to estimate the propagation of red tide phytoplankton species and determine the optimal time interval at which to measure growth yield in eutrophic marine waters where red tides frequently occur. Various red tide phytoplankton species were propagated on a large scale by adding nitrogen or phosphorous. This procedure was useful for estimating the limiting nutrient, elucidating the mechanisms underlying red tides, and determining the levels of increases in organic matter in eutrophic coastal waters. The algal assay using indigenous C. polykrikoides showed that this species did not always propagate, apparently because of very low concentrations of trigger elements that are necessary for its growth, rather than as a result of other environmental characteristics, e.g., water temperature or stress from sampling. In the winter, when water temperatures are lower than in spring, summer, or autumn, maximum propagation and the limiting nutrient could be estimated by measuring phytoplankton biomass at 2 - 3-day intervals. However, in the other seasons, when water temperatures are higher, phytoplankton biomass should be measured at 2-day intervals. In particular, daily monitoring will be required to determine precise growth yields in warm seasons.

KOHONEN NETWORK FOR ADAPTIVE IMAGE COMPRESSION (영상압축을 위한 코넨네트워크)

  • 손형경;이영식;배철수
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.10a
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    • pp.571-574
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    • 2001
  • In our paper, We propose an efficient adaptive coding method using kohonen neural network. An efficient adaptive encoding method using Kohonen net work is discribed through the analysis of those compression methods with the application of the neural network. In order to increase the compression ratio, a image is first divided into 8*8 subimages, then all subimages are transformed by DCT. These DCT sub-blocks are divided into N(4) classes by Kohonen network. Hits are distributed according to the variance of the DCT sub-block. Thus we get N(4)bit allocation matrices. Excellent performance is shown by the computer simulation. so we found that our proposed method is better then classifing subimages by AC energy.

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Genetic Algorithm-based Hardware Resource Mapping Technique for the latency optimization in Wireless Network-on-Chip (무선 네트워크-온-칩에서 지연시간 최적화를 위한 유전알고리즘 기반 하드웨어 자원의 매핑 기법)

  • Lee, Young Sik;Lee, Jae Sung;Han, Tae Hee
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.05a
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    • pp.174-177
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    • 2016
  • Wireless network-on-chip (WNoC) can alleviate critical path problem of existing typical NoCs by integrating radio-frequency module on router. In this paper, core-connection-aware genetic algorithm-based core and WIR mapping methodology at small world WNoC is presented. The methodology could optimize the critical path between cores with heavy communication. The 33% of average latency improvement is achieved compared to random mapping methodology.

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Aging Effects of Silica Slurry and Oxide CMP Characteristics (실리카 슬러리의 에이징 효과 및 산화막 CMP 특성)

  • 이우선;고필주;이영식;서용진;홍광준
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.17 no.2
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    • pp.138-143
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    • 2004
  • CMP (Chemical Mechanical Polishing) technology for global planarization of multilevel interconnection structure has been widely studied for the next generation devices. Among the consumables for CMP process, especially, slurry and their chemical compositions play a very important role in the removal rates and within-wafer non-uniformity (WIWNU) for global planarization ability of CMP process. However, CMP slurries contain abrasive particles exceeding 1 ${\mu}{\textrm}{m}$ size, which can cause micro-scratch on the wafer surface after CMP process. Such a large size particle in these slurries may be caused by particle agglomeration in slurry supply-line. In this work, to investigate the effects of agglomeration on the performance of oxide CMP slurry, we have studied an aging effect of silica slurry as a function of particle size distribution and aging time during one month. We Prepared and compared the self-developed silica slurry by adding of alumina powders. Also, we have investigated the oxide CMP characteristics. As an experimental result, we could be obtained the relatively stable slurry characteristics comparable to aging effect of original silica slurry. Consequently, we can expect the saving of high-cost slurry.

A Study on Structural Safety of Integrated Machine for Grinding Wheel Forming (연삭 휠 형상 복합가공시스템의 구조 안전성에 관한 연구)

  • Lee, Won-Suk;An, Beom-Sang;Kim, Jin-Hyeon;Lee, Jong-Chan;Woo, Bong-Geun;Lee, Young-Sik
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.15 no.2
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    • pp.84-88
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    • 2016
  • This study evaluated the structural safety of a heavy-duty integrated machine for grinding wheel forming. Structural analysis was performed to evaluate the structural safety of the base. The base was designed by dividing the single base and detachable base. The analysis conditions were applied to the own weight and the load of component parts. From the structural analysis results, although the stress of the detachable base was decreased, the amount of deformation was increased. If the deformation of the detachable base decreases, it is expected to be safer than the single base.

Prediction on the Negative Outcomes of Anger in Female Adolescents (청년기 여성의 분노 결과 예측모형)

  • 박영주;한금선;신현정;강현철;천숙희;문소현;이영식;김헌수
    • Journal of Korean Academy of Nursing
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    • v.34 no.1
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    • pp.172-181
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    • 2004
  • Purpose: This study was designed to construct a structural model for explaining negative outcomes of anger in female adolescents. Methods: Data was collected by questionnaires from 199 female adolescents ina female high school in Seoul. Data analysis was done with SAS for descriptive statistics and a PC-LISREL Program for Covariance structural analysis. Results: The fit of the hypothetical model to the data was moderate, thus it was modified by excluding 7 paths and adding free parameters to it. The modified model withthe paths showed a good fit to the empirical data($x^2$ =5.62, p=.69, GFl=.99, AGFl=.97, NFI=.99, NNFI=l.01, RMSR=.02, RMSEA=.00). Trait anger, state anger, and psychosocial problems were found to have a significant direct effect on psychosomatic symptoms. State anger, psychosocial problems, and learning behaviorswere found to have direct effects on depression of female adolescents. Conclusion: The derived modelis considered appropriate for explaining and predicting negative outcomes of anger in female adolescents. Therefore, it can effectively be used as a reference model for further studies and is a suggested direction in nursing practice.

Design of Rehabilitation Program Contents using Motion Detection Sensors (동작인식센서를 이용한 재활 프로그램 콘텐츠 설계)

  • Jang, Jae-Youl;Lee, Young-Sik;Kim, Do-Moon;Lee, Tae-Hee;Choi, Chul-Jae
    • The Journal of the Korea institute of electronic communication sciences
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    • v.13 no.4
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    • pp.903-910
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    • 2018
  • The necessary rehabilitation training for patients with disability currently does not match the actual amount of training conducted, which requires interest in rehabilitation treatment, continued investment and infrastructure for rehabilitation contents, while the most common forms of rehabilitation treatment comprises of art, music, and play treatments. In this paper, we provide a game-style rehabilitation program including audio and visual elements through motion detection process on the patient and design a digital game rehabilitation program that allows different level of management for various categories of disabled people.

Face Recognition Method Robust to Change in Lighting Condition (조명의 변화에 강건한 얼굴인식)

  • Nam, Kee-Hwan;Han, Jun-Hee;Park, Ho-Sik;Lee, Young-Sik;Jung, Yen-Gil;Ra, Sang-Dong;Bae, Cheol-Soo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.1
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    • pp.1137-1140
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    • 2005
  • The work presented in this paper describes a Hidden Markov Model(HMM)-based framework for face recognition and face detection. The observation vectors used to characterize the statics of the HMM are obtained using the coefficients of the Karhuman-Loves Transform(KLT). The face recognition method presented in this paper reduces significantly the computational complexity of previous HMM-based face recognition systems, while slightly improving the recognition rate. In addition, the suggested method is more effective than the exiting ones in face extraction in terms of accuracy and others even under complex changes to the surroundings such as lighting.

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Object Tracking & PTZ camera Control for Intelligent Surveillance System (지능형 감시 시스템을 위한 객체 추적 및 PTZ 카메라 제어)

  • Lee, Young-Sik;Kim, Tae-Woo;Nam, Kee-Hwan;Park, Ho-Sik;Bae, Cheol-Soo
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.1 no.2
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    • pp.65-70
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    • 2008
  • Smart surveillance, is the use of automatic video analysis technologies in video surveillance applications. We present a robust object tracking method using pan-tilt-zoom camera for intelligent surveillance System, As the result of the experiment using 78 vehicle, the success rate of the tracking for moving object & non-moving object werw 97.4% and 91%. and 84.6%. the success rate o PTZ control for license plate image.

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