• Proceedings of the Korean Information Science Society Conference
• /
• 2000.10b
• /
• pp.371-373
• /
• 2000

본 논문에서는 분절 특징을 모수적 궤적 모델을 이용하여 표현하고, 이 특징을 분절 HMM(segmental HMM)의 입력으로 하는 음성 신호의 모델링 방식을 제안한다. 분절 특징은 음성의 경향을 나타내는 궤적으로 표현되고, 그 궤적은 연속되는 프레임 상에서 전이 정보를 포함하도록 디자인 행렬과 다항식의 회귀 함수를 이용하여 구해진다. 이 궤적을 분절 HMM에 적용하기 위하여, 외적 분절 변이와 내적 분절 변이에 대한 확률 분포 표현을 개선하였다. 제안된 방법의 효과를 살펴보기 위하여 TIMIT 데이터 베이스를 이용하여 실험한 결과, 제안된 분절 특징은 음성 신호의 인접한 프레임간의 상관관계를 표현하는 동적 특징과 같은 효과를 보였으며, 1차 미분계수를 포함하여 분절 특징을 구한 경우에는 기존의 특징 표현보다 좋은 성능을 보였다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2004.05a
• /
• pp.1561-1564
• /
• 2004

초고속 유무선 통신망이 확대됨에 따라 디지털 데이터 통신 및 저장 시스템 설계 시 통신채널에서 발생하는 오류를 효율적으로 제어하기 위한 오류정정부호 장치가 중요한 요소가 되었다. 본 논문에서는 기존의 셀룰라 오타마타 기반의 오류정정부호를 개선시킨 이중 오류정정부부호를 설계하는 방법을 제안한다.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.13 no.2
• /
• pp.383-390
• /
• 2018

Since cellular automata(CA) is superior to LFSR in randomness, it is applied as an alternative of LFSR in various fields. However, constructing CA corresponding to a given polynomial is more difficult than LFSR. Cattell et al. and Cho et al. showed that irreducible polynomials are CA-polynomials. And Cho et al. and Sabater et al. gave a synthesis method of 90/150 CA corresponding to the power of an irreducible polynomial, which is applicable as a shrinking generator. Swan characterizes the parity of the number of irreducible factors of a trinomial over the finite field GF(2). These polynomials are of practical importance when implementing finite field extensions. In this paper, we show that the trinomial $x^{2^n-1}+X+1$ ($n{\geq}2$) are CA-polynomials. Also the trinomial $x^{2^a(2^n-1)}+x^{2^a}+1$ ($n{\geq}2$, $a{\geq}0$) are CA-polynomials.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.7 no.3
• /
• pp.118-125
• /
• 2004

The purpose of this study is to decide an appropriate neighborhood and a transition rule of cellular automata by analyzing the past growth process of urban areas in Gimhae. With cellular automata which can manage the change based on the dynamic model and time, this study analyzes the urban growth of Gimhae from 1987 to 2001. Also, through the simulation of different types for neighborhood and transition rules, we can find the appropriate neighborhood and the transition rule for Gimhae. In conclusion, the forecast of physical urban growth pattern is more accurate under conditions when the number of matrixes for the neighborhood is small, the shape of the neighborhood is rectangular, "${\alpha}$" value, which control the pace of urban growth, is low and the transition possibility ($P_{ij}$) is high.

• KIPS Transactions on Computer and Communication Systems
• /
• v.11 no.4
• /
• pp.105-112
• /
• 2022

Recently, many studies using reinforcement learning-based autoscaling have been performed to make autoscaling policies that are adaptive to changes in the environment and meet specific purposes. However, training the reinforcement learning-based Horizontal Pod Autoscaler(HPA) policy in a real environment requires a lot of money and time. And it is not practical to retrain the reinforcement learning-based HPA policy from scratch every time in a real environment. In this paper, we implement a reinforcement learning-based HPA in Kubernetes, and propose a transfer leanring technique using a queuing model-based simulation to accelerate the training of a reinforcement learning-based HPA policy. Pre-training using simulation enabled training the policy through simulation experience without consuming time and resources in the real environment, and by using the transfer learning technique, the cost was reduced by about 42.6% compared to the case without transfer learning technique.

• The Korean Journal of Applied Statistics
• /
• v.14 no.1
• /
• pp.25-37
• /
• 2001

The marginal model is proposed for the analysis of data which have c(2: 3) categories in the 3 x 3 cross-over trials with three periods and three treatments. This model could be used for the counterpart of the Kenward-Jones' joint probability one and should be the generalization of Balagtas et ai's univariate marginal logits one, which analyze the treatment effects in the 3 x 3 cross-over trials with binary response variables[Kenward and Jones(1991), Balagtas et al(1995)]. The model equations for the marginal probability are constructed by the three types of link functions. The methods would be given for making of the link function matrices and model ones, and the estimation of parameters shall be discussed. The proposed model is applied to the analysis of Kenward and Jones' data.

• Journal of the Korean Vacuum Society
• /
• v.16 no.4
• /
• pp.273-278
• /
• 2007

For the simulation of active region in the quantum cascade lasers (QCL), we solved Schrodinger equation utilizing Runge-Kutta method and Shotting method. Wavelength, phonon resonant energy, and dipole matrix element were simulated with the variation of active region thickness. As a result of such simulation, it was suggested the tolerance range of epi-layer thickness error when 3-quantum well QCL structures are grown.

• Spatial Information Research
• /
• v.5 no.2
• /
• pp.177-183
• /
• 1997

S1he concept of a class in the land-use classification system can be equally applied to a class in the land-use-change classification. The maximum likelihood method using linear discriminant function and Markov transition matrix method were integrated to a synthetic modeling effort in order to project spatial allocation of land-use-change and quantitative assignment of that prediction as a whole. The algorithm of both the multivariate discriminant function and the Markov chain matrix were discussed and the test of synthetic model on the study area was resulted in the projection of '90 year as well as '95 year land -use classification. The accuracy and the issue of modeling improvement were discussed eventually.

• New & Renewable Energy
• /
• v.18 no.1
• /
• pp.17-28
• /
• 2022

This paper presents an effective Markov transition matrix (EMTM), which will be used to calculate the wind speed at the target site in a wind farm to accurately predict wind energy production. The existing MTS prediction method using a Markov transition matrix (MTM) exhibits a limitation where significant prediction variations are observed owing to random selection errors and its bin width. The proposed method selects the effective states of the MTM and refines its bin width to reduce the error of random selection during a gap filling procedure in MTS. The EMTM reduces the level of variation in the repeated prediction of wind speed by using the coefficient of variations and range of variations. In a case study, MTS exhibited better performance than other MCP models when EMTM was applied to estimate a one-day wind speed, by using mean relative and root mean square errors.

• The Journal of the Acoustical Society of Korea
• /
• v.13 no.5
• /
• pp.24-31
• /
• 1994

In this paper, we study continuous speech recognition of Korean language using acoustic models of word juncture coarticulation. To alleviate the performance degradation due to coarticulation problems, we use context-dependent units that model inter-word transitions in addition to intra-word transitions. In all cases the initial phone of each word has to be specified for each possible final phone of the previous word similarly for the final phone of each word. To improve the robustness of the HMM parameters, the covariance matrix is smoothed. We also use position-dependent units to improve the discriminative power between units. Simulation results show that when the improved models of word juncture coarticulation are used. the recognition performance is considerably improved compared to the baseline system using only intra-word units.