• Title/Summary/Keyword: Symbols

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A Study on Symbol-based Decoding for Turbo Codes (심볼 단위로 복호화가 이루어지는 터보부호에 관한 연구)

  • 김태국;심용걸
    • Proceedings of the IEEK Conference
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    • 2001.06a
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    • pp.273-276
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    • 2001
  • In this thesis we propose symbol-based decoding for turbo codes which is used SOVA as a decoding algorithm. The proposed turbo codes that is interleaved on symbol-by-symbol basis and inputted as n-bit symbols to the decoder. This method makes that the stages of the original trellis are merged together and the trellis depth is reduced by 1/n. We research turbo codes with symbol size n=2 in this paper and its performance.

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Character Segmentation in Chinese Handwritten Text Based on Gap and Character Construction Estimation

  • Zhang, Cheng Dong;Lee, Guee-Sang
    • International Journal of Contents
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    • v.8 no.1
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    • pp.39-46
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    • 2012
  • Character segmentation is a preprocessing step in many offline handwriting recognition systems. In this paper, Chinese characters are categorized into seven different structures. In each structure, the character size with the range of variations is estimated considering typical handwritten samples. The component removal and merge criteria are presented to remove punctuation symbols or to merge small components which are part of a character. Finally, the criteria for segmenting the adjacent characters concerning each other or overlapped are proposed.

A study of auxiliary schedules in classification (분류표에서 사용하는 보조표에 대한 연구)

  • 정해성
    • Journal of Korean Library and Information Science Society
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    • v.28
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    • pp.193-218
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    • 1998
  • The purpose of this study is to analyze and compare of the structure of auxiliary schedules using in DDC, UDC, CC and BC. Auxiliary schedule whish are a n.0, ppended to schedule of all schemes of classification. They consist of items of form of presentation relationship, time, place, languages, racial, ethnic, national groups and persons and phase relation and the symbols of the different items can be added to classification numbers.

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A Computer-Aided Design Checking System for Mechanical Drawings Drawn with CAD Systems (CAD시스템을 이용하여 작성한 도면의 설계검증)

  • 이성수;소야민랑
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1994.10a
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    • pp.847-851
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    • 1994
  • Existing CAD systems do not provide the advanced function for systematic checking of design and drafting errors in mechanical drawings. This paper describes a method for systematic checking in mechanical drawings. The checking items are deficiency and redundancy of dimensions, input-errors in dimension figures and symbols, etc. Checking for deficiency and redundancy of global dimensions has been performed applying Graph Theory. This system has been applied to several examples and we have confirmed the feasibility of this design checking method.

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Computer Aided Design Verification System of CAD Drawings Drawn with CAD System(The Case of Considering to Annular Parts) (CAD시스템을 이용하여 작성한 도면의 설계검증시스템(회전체를 고려한 경우))

  • 이성수
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.11a
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    • pp.593-597
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    • 1996
  • This paper describes a method for drawing check of dimension errors, such as deficiency and redundancy of dimensions, input-errors in dimension figures and symbols, etc. The logic for finding dimensional errors is written by using the Turbo C language. Checking for deficiency and redundancy of global dimensions has been performed applying Graph Theory. Especialy, this paper gives an account of checking method for annular parts.

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Alias Component Permutation Matrices (ACPM) for the $3^n$ Parallel Fractional Factorial Design

  • Um, Jung-Koog
    • Journal of the Korean Statistical Society
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    • v.9 no.1
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    • pp.1-12
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    • 1980
  • A parallel flats faraction for the $3^n$ factorial experiment is symbolically written as $At = C(r\timesf)$ where $A(r\timesn)$ is of rank r. The A-matrix partitions the nonnegligible effects into $(3^{n-r}-1)/2+1$ alias sets. The $U_i$ effects in the i-th alias set are related pairwise by elements from $S_3$, the symmetric group on three symbols. For each alias set the f flats produce an $f \times u_i$ alias componet permutation matrices (ACPM) with elements from $S_3$. All the information concerning the relationships among levels of the effects is contained in the ACPM.

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Non-Pilot-Aided Timing Offset Estimation for OFDM Systems with Frequency Diversity

  • Yang, Hyun;You, Young-Hwan
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2006.11a
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    • pp.175-177
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    • 2006
  • This letter deals with non-pilot-aided symbol timing estimation methods in an orthogonal frequency division multiplexing (OFDM) system. To do this, OFDM system uses a frequency diversity scheme over two consecutive data symbols. Our approach can be viewed as an expansion of Schmidl's and Minn's correlation methods. Using the OFDM signal equipped with frequency diversity, however, symbol timing is accurately estimated without additional training symbol and a second-order diversity gain is achieved.

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A Study on Multi-Carrier CDMA in Rayleigh Fading Channel (레일레이 폐이딩환경에서의 다중반송파 CDMA방식에 관한 연구)

  • 홍우상;한영열
    • Proceedings of the Korea Society for Industrial Systems Conference
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    • 1997.11a
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    • pp.127-135
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    • 1997
  • In this paper, we apply a digital modulation scheme called Multi-Carrier Code Division Multiple Access (MC-CDMA) in which data symbols are transmitted at multiple subcarriers. Each subcarrier is encoded with a phase offset of -π or π based on a pseudo-random noise(PN) sequence. MC-CDMA scheme is introduced to combat against the multipath fading. We annalize above system and derive the average probability of error in AWGN and Rayleigh fading environment.

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A Study on the Conformity of KS Standards according to Agreement on WTO/TBT (WTO/TBT 협정에 따른 KS 규격의 부합화에 관한 연구)

  • 김진규
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.26 no.4
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    • pp.12-22
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    • 2003
  • The purposes of this study are to investigate the conformity of Korean Standards(KS) according to agreement on WTO/TBT, and to propose systematic frameworks of preparation, adoption, and application for KS in our enterprises. Significant changes in this establishment, revision, and abrogation include the following divisions; i) statistics-vocabulary and symbols, ii) Shewhart control chart, iii) statistical interpretation of data, iv) sampling procedures for inspection by attributes, v) sequential sampling plans for inspection.

Development of Fatigue Strength Database for Windows 95 (윈도우환경에서의 피로강도 데이터베이스 구축)

  • 강재윤;송지호;박준협
    • Proceedings of the KSR Conference
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    • 1998.05a
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    • pp.323-329
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    • 1998
  • Fatigue strength database system was developed for Windows 95 on personal computer. The relational database management system Visual Foxpro 5.0 was used. The database system developed contains 3,147 S-N curves and 311 $\varepsilon$-N ones for 437 material symbols and has the ability to search data by material symbol that each specification marks differently. Visual Basic 5.0 was used for graphic presentation and statistical treatment of the data searched.

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