• Title/Summary/Keyword: Asymmetric distribution

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Transform Methods for PAM Signals as Asymmetric Distribution and Performance Comparison of Bicepstrum Blind Equalizer using Asymmetric Distribution (PAM 신호의 비대칭 분포를 형성하기 위한 방법과 이를 이용한 3차 통계 자력 등화기의 성능 비교)

  • 정교일;임제택
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.6
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    • pp.54-63
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    • 1996
  • We propose a 3rd order blind equalizer that incorporates a new transform method using either square root operation ($\sqrt{x]$) or reciprocal operation (1/x) in order to transform symmetric distribution of PAM signals at the transmitter, to asymmetric one. At the receiver, either the square operation or the reciprocal operation is needed to recover the asymmetrically transformed signals to the original ones after eualization. The reslts of the computer simulation, using the new method are better than the existing transform method using natural logarithm operation by the maximum of 8 dB in MSE. In addition, as the skewness of the asymmetrically transformed distribution has small values, the performances are improved.

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Validity assessment of VaR with Laplacian distribution (라플라스 분포 기반의 VaR 측정 방법의 적정성 평가)

  • Byun, Bu-Guen;Yoo, Do-Sik;Lim, Jongtae
    • Journal of the Korean Data and Information Science Society
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    • v.24 no.6
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    • pp.1263-1274
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    • 2013
  • VaR (value at risk), which represents the expectation of the worst loss that may occur over a period of time within a given level of confidence, is currently used by various financial institutions for the purpose of risk management. In the majority of previous studies, the probability of return has been modeled with normal distribution. Recently Chen et al. (2010) measured VaR with asymmetric Laplacian distribution. However, it is difficult to estimate the mode, the skewness, and the degree of variance that determine the shape of an asymmetric Laplacian distribution with limited data in the real-world market. In this paper, we show that the VaR estimated with (symmetric) Laplacian distribution model provides more accuracy than those with normal distribution model or asymmetric Laplacian distribution model with real world stock market data and with various statistical measures.

How Does Corporate Social Responsibility Affect Asymmetric Information: Evidence from Korean Retail Industry

  • Kim, Sang-Su;Lee, Jeong-Hwan
    • Journal of Distribution Science
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    • v.17 no.2
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    • pp.5-11
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    • 2019
  • Purpose - This paper examines how corporate social responsibility of the Korean retail industry affects the degree of asymmetric information. Recent theories predict that a firm's active engagement in socially responsible activities lowers the degree of asymmetric information of the firm. Research design, data, and methodology - This paper uses the sum of environmental and social scores (ES), published by the Korean Corporate Governance Service in order to proxy the degree of socially responsible management practices of Korean retail firms. This paper uses the ordinary least square method to investigate the above predictions. The publicly traded Korea retail firms listed in the Korean Exchange are analyzed from 2011 to 2016. To measure the degree of asymmetric information, this paper adopts the analyst dispersion and price impact measures. Results - This paper shows that the ES score has significantly positive relationships with these two measures of information asymmetry. The environmental score seems to increase the analyst dispersion measure and the social score appears to raise the price impact measure mores significantly. Conclusions - The results do not support the prior theory expecting a negative relationship between corporate social responsibility and the degree of asymmetric information. Environmental and social scores are found to affect the measures of information asymmetry differently.

Against the Asymmetric CP- V2 Analysis of Old English

  • Yoon, Hee-Cheol
    • Korean Journal of English Language and Linguistics
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    • v.4 no.2
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    • pp.117-149
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    • 2004
  • The paper is to argue against the asymmetric CP-V2 analysis of Old English, according to which finite verbs invariably undergo movement into a clause-final T within subordinate clauses and reach the functional head C within main clauses. The asymmetric CP-V2 analysis, first of all, faces difficulty in explaining a wide range of post-verbal elements within subordinate clauses. To resolve the problem, the analysis has to abandon the obligatoriness of V-to-T movement or introduce various types of extraposition whose status is dubious as a legitimate syntactic operation. Obligatory V-to-T movement in Old English lacks conceptual justification as well. Crosslinguistic evidence reveals that morphological richness in verbal inflection cannot entail overt verb movement. Moreover, the operation is always string-vacuous under the asymmetric CP- V2 analysis and has no effect at the interfaces, in violation of the principle of economy. The distribution of Old English finite verbs in main clauses also undermines the asymmetric CP-V2 analysis. Conceptually speaking, a proper syntactic trigger cannot be confirmed to motivate obligatory verb movement to C. The operation not only gets little support from nominative Case marking, the distribution of expletives, or complementizer agreement but also requires the unconvincing stipulation that expletives as well as sentence-initial subjects result from string-vacuous topicalization. Finally, textual evidence testifies that Old English sometimes permits non-V2 ordering patterns, many of which remain unexplained under the asymmetric CP-V2 analysis.

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Analysis of Subthreshold Swing for Doping Distribution Function of Asymmetric Double Gate MOSFET (도핑분포함수에 따른 비대칭 MOSFET의 문턱전압이하 스윙 분석)

  • Jung, Hakkee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.5
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    • pp.1143-1148
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    • 2014
  • This paper has analyzed the change of subthreshold swing for doping distribution function of asymmetric double gate(DG) MOSFET. The basic factors to determine the characteristics of DGMOSFET are dimensions of channel, i.e. channel length and channel thickness, and doping distribution function. The doping distributions are determined by ion implantation used for channel doping, and follow Gaussian distribution function. Gaussian function has been used as carrier distribution in solving the Poisson's equation. Since the Gaussian function is exactly not symmetric for top and bottome gates, the subthreshold swings are greatly changed for channel length and thickness, and the voltages of top and bottom gates for asymmetric double gate MOSFET. The deviation of subthreshold swings has been investigated for parameters of Gaussian distribution function such as projected range and standard projected deviation in this paper. As a result, we know the subthreshold swing is greatly changed for doping profiles and bias voltage.

Diagnosis of Observations after Fit of Multivariate Skew t-Distribution: Identification of Outliers and Edge Observations from Asymmetric Data

  • Kim, Seung-Gu
    • The Korean Journal of Applied Statistics
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    • v.25 no.6
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    • pp.1019-1026
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    • 2012
  • This paper presents a method for the identification of "edge observations" located on a boundary area constructed by a truncation variable as well as for the identification of outliers and the after fit of multivariate skew $t$-distribution(MST) to asymmetric data. The detection of edge observation is important in data analysis because it provides information on a certain critical area in observation space. The proposed method is applied to an Australian Institute of Sport(AIS) dataset that is well known for asymmetry in data space.

Copula-based common cause failure models with Bayesian inferences

  • Jin, Kyungho;Son, Kibeom;Heo, Gyunyoung
    • Nuclear Engineering and Technology
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    • v.53 no.2
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    • pp.357-367
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    • 2021
  • In general, common cause failures (CCFs) have been modeled with the assumption that components within the same group are symmetric. This assumption reduces the number of parameters required for the CCF probability estimation and allows us to use a parametric model, such as the alpha factor model. Although there are various asymmetric conditions in nuclear power plants (NPPs) to be addressed, the traditional CCF models are limited to symmetric conditions. Therefore, this paper proposes the copulabased CCF model to deal with asymmetric as well as symmetric CCFs. Once a joint distribution between the components is constructed using copulas, the proposed model is able to provide the probability of common cause basic events (CCBEs) by formulating a system of equations without symmetry assumptions. In addition, Bayesian inferences for the parameters of the marginal and copula distributions are introduced and Markov Chain Monte Carlo (MCMC) algorithms are employed to sample from the posterior distribution. Three example cases using simulated data, including asymmetry conditions in total failure probabilities and/or dependencies, are illustrated. Consequently, the copula-based CCF model provides appropriate estimates of CCFs for asymmetric conditions. This paper also discusses the limitations and notes on the proposed method.

The Effect of Asymmetric Electrode Structure on the Emission Efficiency in ac Gas Discharge (비대칭 전극구조가 교류형 기체 방전의 발광효율에 미치는 영향)

  • Seo, Jeong-Hyun;Shin, Bhum-Jae
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.5
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    • pp.732-738
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    • 2015
  • In ac discharge, emission efficiency shows an time-varying characteristics during discharge. The phenomenon is caused by the potential distribution changes during the discharge, which indicates that a specific potential distribution can contribute to a high improvement of the emission efficiency. To create an artificial environment for a potential distribution favorable to emission efficiency, we used the asymmetric electrode structure and proved the capability. Our results showed that the ratio of the area of anode to cathode became larger, the emission efficacy was greatly improved.

Asymmetric Vortices around a Body at High Angle of Attack Subsonic Flow (아음속 유동하의 고 받음각 물체 주위의 비대칭 와류 특성 연구)

  • Park, Mee-Young;Kim, Wan-Sub;Lee, Jae-Woo;Park, Soo-Hyung
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03b
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    • pp.33-38
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    • 2008
  • Numerical investigation of asymmetric vortices at high angles of attack subsonic flow is performed using three-dimensional Navier-Stokes equations. A small bump has been carefully selected and attached near the nose of an ogive cylinder to simulate symmetric vortices. Selected bump shape does develop asymmetric vortices and is verified using Lamont's experimental results. By changing the angle of attack, Reynolds numbers, and Mach numbers, the characteristics of asymmetric vortices are observed. The angle of attack which contributes significantly to the generation of asymmetric vortices are over 30 degrees. By increasing Mach number and Reynolds number asymmetric vortices, hence the side forces show decreasing trend..

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Study on the Design of Asymmetric Lighting with Uniform Illumination Over a Large Area at Short Distance (단거리 조사 시 넓은 면적에 균일한 조명도를 가지는 비대칭 조명 광학계 설계 연구)

  • Kang, Dong-Hwa;Jung, Mee-Suk
    • Korean Journal of Optics and Photonics
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    • v.31 no.4
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    • pp.183-190
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    • 2020
  • In this paper, the illuminating optics of asymmetric light distribution was studied, which allowed the light distribution to be uniform even for short-range irradiation on a wide illumination area. In the case of a light installed at a short distance, the light is not diffused enough because of the short irradiation distance. For this reason, it is difficult to satisfy uniformity of illumination. In addition, lighting design for asymmetric distribution is required because the lighting device is installed tilted, for visibility. Therefore, the design of lighting systems with asymmetric light distribution could achieve uniform illumination of the target surface even under short-distance irradiation. This was then applied to the license lamp, a lighting system featuring short light irradiation distance, to confirm that it satisfies the legal standards.