• Title/Summary/Keyword: Root density

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Rate-Compatible LDPC Codes Based on the PEG Algorithm for Relay Communication Systems

  • Zhou, Yangzhao;Jiang, Xueqin;Lee, Moon Ho
    • Journal of Communications and Networks
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    • v.17 no.4
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    • pp.346-350
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    • 2015
  • It is known that the progressive edge-growth (PEG) algorithm can be used to construct low-density parity-check (LDPC) codes at finite code lengths with large girths through the establishment of edges between variable and check nodes in an edge-by-edge manner. In [1], the authors derived a class of LDPC codes for relay communication systems by extending the full-diversity root-LDPC code. However, the submatrices of the parity-check matrix H corresponding to this code were constructed separately; thus, the girth of H was not optimized. To solve this problem, this paper proposes a modified PEG algorithm for use in the design of large girth and full-diversity LDPC codes. Simulation results indicated that the LDPC codes constructed using the modified PEG algorithm exhibited a more favorable frame error rate performance than did codes proposed in [1] over block-fading channels.

Desalinization Effect of Subsurface Drainage System with Rice Hull Packing (왕겨충전에 따른 암거의 제염 효과)

  • Lee, Seung-Heon;An, Yeoul;Yoo, Sun-Ho;Jung, Yeong-Sang
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.43 no.5
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    • pp.63-69
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    • 2001
  • The main purpose of this study is to seek desalinization effect of subsurface drainage system with rice hull packing in Dae-Ho Reclaimed Land. After 4 years installed sub-surface drainage system, distribution of drained water electric conductivity (ECw) was 4.43~12.78 ds/m. The soil profile showed partial development of the soil structure and compaction of subsoils with increased bulk density. The bulk density of the subsoil was 1.42~1.66 g/cm$^3$, which might limit root growth. The soil color changed near the drainage pipe line. Distribution of soil extract solution ECe and SAR as subsurface drainage pipe position and drainage canal distance showed desalinization effect of subsurface drainage system with rice hull packing as widening effective zone of subsurface drainage pipe.

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Microprocessor Control of a Prosthetic Arm by EMG Pattern Recognition (EMG 패턴인식을 이용한 인공팔의 마이크로프로세서 제어)

  • Hong, Suk-Kyo
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.33 no.10
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    • pp.381-386
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    • 1984
  • This paper deals with the microcomputer realization of EMG pattern recognition system which provides identification of motion commands from the EMG signals for the on-line control of a prosthetic arm. A probabilistic model of pattern is formulated in the feature space of integral absolute value(IAV) to describe the relation between a motion command and the location of corresponding pattern. This model enables the derivation of sample density function of a command in the feature space of IAV. Classification is caried out through the multiclass sequential decision process, where the decision rule and the stopping rule of the process are designed by using the simple mathematical formulas defined as the likelihood probability and the decision measure, respectively. Some floating point algorithms such as addition, multiplication, division, square root and exponential function are developed for calculating the probability density functions and the decision measure. Only six primitive motions and one no motion are incorporated in this paper.

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Wakeby Distribution and the Maximum Likelihood Estimation Algorithm in Which Probability Density Function Is Not Explicitly Expressed

  • Park Jeong-Soo
    • Communications for Statistical Applications and Methods
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    • v.12 no.2
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    • pp.443-451
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    • 2005
  • The studied in this paper is a new algorithm for searching the maximum likelihood estimate(MLE) in which probability density function is not explicitly expressed. Newton-Raphson's root-finding routine and a nonlinear numerical optimization algorithm with constraint (so-called feasible sequential quadratic programming) are used. This algorithm is applied to the Wakeby distribution which is importantly used in hydrology and water resource research for analysis of extreme rainfall. The performance comparison between maximum likelihood estimates and method of L-moment estimates (L-ME) is studied by Monte-carlo simulation. The recommended methods are L-ME for up to 300 observations and MLE for over the sample size, respectively. Methods for speeding up the algorithm and for computing variances of estimates are discussed.

A Comparative Study on the Spatial Statistical Models for the Estimation of Population Distribution

  • Oh, Doo-Ri;Hwang, Chul Sue
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.3
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    • pp.145-153
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    • 2015
  • This study aims to accurately estimate population distribution more specifically than administrative unites using a RK (Regression-Kriging) model. The RK model is the areal interpolation technique that involves linear regression and the Kriging model. In order to estimate a population’s distribution using a sample region, four different models were used, namely; a regression model, RK model, OK (Ordinary Kriging) model and CK (Co-Kriging) model. The results were then compared with each other. Evaluation of the accuracy and validity of evaluation analysis results were the basis RMSE (Root Mean Square Error), MAE (Mean Absolute Error), G statistic and correlation coefficient (ρ). In the sample regions, every statistic value of the RK model showed better results than other models. The results of this comparative study will be useful to estimate a population distribution of the metropolitan areas with high population density

Effects of Isatis indigitica on Anti-lipid Peroxidation and Low Density Lipoprotein Oxidation (판람근의 지질과산화 및 저밀도지단백산화에 미치는 영향)

  • 장현진;양기숙
    • YAKHAK HOEJI
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    • v.46 no.6
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    • pp.448-451
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    • 2002
  • Isatis indigotica is commonly used as traditional chinese medicine for antipyretic, antiviral, and detoxifying purpose in China. In order to examine whether it prevents lipid peroxidation, root of Isatis indigotica was extracted with methanol and fractionated with hexane, ethyl acetate, butanol and water. The activity was evaluated by DPPH method and lipid peroxidation in rat liver homogenate and C $u^{++}$ -induced oxidated LDL. The results showed that ethyl acetate fraction and indigo, which is known as its constituent, had significantly anti-lipid peroxidative effects.s.

Antioxidative Effects of Cichorium intybus Root Extract on LDL (Low Density Lipoprotein) Oxidation

  • Kim, Tae-Woong;Yang, Ki-Sook
    • Archives of Pharmacal Research
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    • v.24 no.5
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    • pp.431-436
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    • 2001
  • The water extract of Cichorium intybus (WECI) showed a remarkable antioxidative effect on LDL, and inhibitory effects on the production of thiobarbituric acid reactive substance and the Degradation of fatty acids in LDL. Vitamin 1 and unsaturated fatty acids in LDL were protected by adding WECI from the effects of metal catalyzed LDL oxidation. From the results obtained, we conclude that LDL oxidation is inhibited in vitro by the addition of WECI, and that LDL is protected by WECI from oxidative attack, as shown by agarose gel electrohporesis.

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ANALYSIS OF THE BEHAVIOR OF LIMITING SPECTRAL DENSITY FUNCTION OF LARGE DIMENSIONAL RANDOM MATRICES

  • Choi, Sang-Il
    • Journal of applied mathematics & informatics
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    • v.16 no.1_2
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    • pp.483-488
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    • 2004
  • Results on the analytic behavior of the limiting spectral distribution of large dimensional random matrices, studied in Marcenko and Pastur [2], are derived. Using the Stieltjes transform, it is shown that the limiting distribution has a continuous derivative away from zero, the derivative being analytic whenever it is positive [3]. In the present paper, it is derived that the behavior of it resembles the behavior of a square root function near the boundary of its support.

Studies on the Establishment of Cultural Fractice for $\underline{Angelica\;tenuissima}$ NAKAI II. Influence of Planting Density and Fertilizer Level on Growth and Root Yield of $\underline{Angelica\;tenuissima}$ NAKAI (고본(Angelica tenuissima Nakai)의 재배법 확립에 관한 연구 II. 재식밀도와 시비량이 고본의 생육 및 수량에 미치는 영향)

  • Choi E. O.;Seo J. S.;Jeong B. C.;Kang C. W.;Huh B. L.
    • Proceedings of the Korean Society of Crop Science Conference
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    • 1990.05a
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    • pp.118-119
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    • 1990
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