• Journal of Information Processing Systems
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• 제10권4호
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• pp.523-542
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• 2014

One-dimensional arrays with subscripts formed by induction variables in real programs appear quite frequently. For most famous data dependence testing methods, checking if integer-valued solutions exist for one-dimensional arrays with references created by induction variable is very difficult. The I test, which is a refined combination of the GCD and Banerjee tests, is an efficient and precise data dependence testing technique to compute if integer-valued solutions exist for one-dimensional arrays with constant bounds and single increments. In this paper, the non-continuous I test, which is an extension of the I test, is proposed to figure out whether there are integer-valued solutions for one-dimensional arrays with constant bounds and non-sing ularincrements or not. Experiments with the benchmarks that have been cited from Livermore and Vector Loop, reveal that there are definitive results for 67 pairs of one-dimensional arrays that were tested.

• 대한수학회논문집
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• 제9권2호
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• pp.327-329
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• 1994

The Dirichlet problem (DP) on the upper half plane {z = x ＋ iy : y > 0} is to find a real-valued harmonic function u(x, y) satisfying u(x, 0) = g(x) almost everywhere for some reasonably nice function g defined on the real line, which is called the data on the boundary for (DP).(omitted)

• Journal of Electrical Engineering and Technology
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• 제13권4호
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• pp.1715-1723
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• 2018

This work investigates the performance of fully complex- valued radial basis function network(FC-RBF) and complex extreme learning machine (CELM) based neural approaches for classification of power quality disturbances. This work engages the use of S-Transform to extract the features relating to single and combined power quality disturbances. The performance of the classifiers are compared with their real valued counterparts namely extreme learning machine(ELM) and support vector machine(SVM) in terms of convergence and classification ability. The results signify the suitability of complex valued classifiers for power quality disturbance classification.

• Communications for Statistical Applications and Methods
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• 제25권1호
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• pp.29-42
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• 2018

We combine the integer-valued GARCH(1, 1) model with a generalized regime-switching model to propose a dynamic count time series model. Our model adopts Markov-chains with time-varying dependent transition probabilities to model dynamic count time series called the generalized regime-switching integer-valued GARCH(1, 1) (GRS-INGARCH(1, 1)) models. We derive a recursive formula of the conditional probability of the regime in the Markov-chain given the past information, in terms of transition probabilities of the Markov-chain and the Poisson parameters of the INGARCH(1, 1) process. In addition, we also study the forecasting of the Poisson parameter as well as the cumulative impulse response function of the model, which is a measure for the persistence of volatility. A Monte-Carlo simulation is conducted to see the performances of volatility forecasting and behaviors of cumulative impulse response coefficients as well as conditional maximum likelihood estimation; consequently, a real data application is given.

• 대한전자공학회논문지SD
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• 제46권3호
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• pp.10-19
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• 2009

본 논문에서는 다중위상래핑과 실수값 함수를 이용하는 효율적인 광 워터마킹을 제안하였다. 원 영상 삽입 과정에서 숨겨야 될 두 원 영상을 제로 패딩 시켜서 입력 평면의 두 개의 사분면에 하나씩 위치시킨 후 푸리에 변환을 수행하고 다중위상래핑을 적용하여 무작위 정 실수 값을 가지는 패턴을 생성시킨 후 하나의 실수부를 취하여 복호화 키를, 두 패턴 모두의 허수부의 합을 취하여 은닉영상을 생성시킨다. 위에서 생성된 은닉영상을 인간 시각으로는 감지 할 수 없도록 감쇄화 시킨 후 커버 영상과 일차 선형 변환 시켜서 배포영상을 제작한다. 복호화 과정에서는 배포영상과 복호화 키가 곱해져서 광학적인 역 푸리에 변환을 수행하고 출력 평면에서 원점에 대하여 대칭인 원영상이 간단히 복원된다. 컴퓨터 모의 실험과 광실험을 통하여 제안된 워터마킹이 광학적인 시스템에 적용 가능함을 확인하였다.

• 전자공학회논문지C
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• 제35C권1호
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• pp.42-54
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• 1998

For decreasing intersymbol interference (ISI) due to band-limited channels in digitalcommunication, the uses of equalization techniques are necessary. Among the useful adaptive equalization techniques, because of their ease of implementation and nonlinear capabilites, the neural networks have been used as an alternative for effectively dealing with the channel distortion. In this paepr, a complex-valued multilayer percepron is proposed as a nonlinear adaptive equalizer. After the important properties that a suitable complex-valued activation function must possess are discussed, a new complex-valued activation function is developed for the proposed schemes to deal with M-ary QAM signals of any constellation sizes. It has been further proven that by the nonlinear transformation of the proposed function, the correlation coefficient between the real and imaginary parts of input data decreases when they are jointly Gaussian random variables. Lastly, the effectiveness of the proposed scheme is demonstrated by simulations. The proposed scheme provides, compared with the linear equalizer using the least mean squares (LMS) algorith, an interesting improvement concerning Bit Error Rate (BER) when channel distortions are nonlinear.

• 전기학회논문지P
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• 제62권2호
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• pp.84-89
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• 2013

In this paper, we propose interface circuits for reducing power consumption and EMI when sequences of data from LCD controller to LCD driver IC by transmitting two bit data during one clock period. The proposed circuits are operated in current mode, which is different from conventional voltage-mode signaling techniques, and also employ threshold technique of Modified-LVDS(Low Voltage Differential Signaling) method. We have simulated the proposed circuits using H-SPICE tool for performance analysis of the proposed method. The simulation results show that the proposed circuits provide a faster transmission speed and stronger noise immunity than the conventional LVDS circuits. It might be suitable for the real-time transmission of huge image data in LCD system.

• Communications for Statistical Applications and Methods
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• 제27권6호
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• pp.675-688
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• 2020

In survival analysis of observational data, the inverse probability weighting method and the Cox proportional hazards model are widely used when estimating the causal effects of multiple-valued treatment. In this paper, the two kinds of weights have been examined in the inverse probability weighting method. We explain the reason why the stabilized weight is more appropriate when an inverse probability weighting method using the generalized propensity score is applied. We also emphasize that a marginal hazard ratio and the conditional hazard ratio should be distinguished when defining the hazard ratio as a treatment effect under the Cox proportional hazards model. A simulation study based on real data is conducted to provide concrete numerical evidence.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2008년도 한국컴퓨터종합학술대회논문집 Vol.35 No.1 (A)
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• pp.122-123
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• 2008

• 응용통계연구
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• 제28권1호
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• pp.115-122
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• 2015

본 연구에서는 정수값을 갖는 계수 시계열의 조건부 이차적률인 변동성(volatility)을 다루고 있다. 여러 가지 정수값 GARCH, 즉, INGARCH 모형들을 소개하고 계수 시계열인 국내 풍진발생건수에 적용시켜 보았다. 과산포(over-dispersion)와 영과잉(zero-inflation)현상을 계수 시계열의 변동성 분석 입장에서 살펴보았고 향후 분석 모형으로서 영과잉(zero-inflation) INGARCH 모형인 ZI-INGARCH 모형을 살펴보았다.