• The Korean Journal of Applied Statistics
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• v.32 no.1
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• pp.1-13
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• 2019

An adaptive seamless Phase II/III clinical trial design enables a reduction in the sample size (in comparison to a conventional design) that also shortens the clinical development time. It is also very effective in clinical trials since it can have higher statistical power than Phase III alone. In this study, we use extensive simulation studies to compare several multiple hypothesis testing methods that can help select the best doses in a Phase II study along with several methods to combine p-values of the Phase II and Phase III study.

• The KIPS Transactions:PartC
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• v.12C no.1 s.97
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• pp.63-68
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• 2005

In this paper, performance of a maximum-likelihood modulation classification for quadrature amplitude modulation (QAM) is studied. Unlike previous works, the relative classification performance with respect to the available modulations and performance limit with single-sample observation are presented. For those purposes, all constellations are set to have the same minimum Euclidean distance between symbols so that a smaller constellation is a subset of the larger ones. And only one sample of received waveform is used for multiple hypothesis test. As a result, classification performance is improved with increase in signal-to-noise ratio in all the experiments. Especially, when the true modulation format used in the transmitter is 4 QAM, almost perfect classification can be achieved without any additional information or observation samples. Though the possibility of false classification due to the symbols shared by subset constellations always exists, correct classification ratio of $80{\%}$ can be obtained with the single-sample observation when the true modulation formats are 16 and 64 QAM.

• Journal of the Korean Society of Propulsion Engineers
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• v.6 no.4
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• pp.7-13
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• 2002

In this study, the mathematical model on the various complicated levels of the viscous liquid flows in the symmetric channel with the complicated shape was introduced and the assumptions applied to the simplified model was proposed. To analyse the steady cavitation flow, axis transform of physical region to non-dimensional region was performed, and multigrid were generated. Using this model, the steady cavitation flow was calculated, and good coincidence between experiment and calculation was achieved.

• Korean Journal of Cognitive Science
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• v.17 no.2
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• pp.103-118
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• 2006

The main purpose of this paper is to investigate the effects of discourse topic and morpho-syntactic verbal information on the resolution of null pronouns in the Korean narrative text within the framework of the construction-integration theory (Kintsch, 1988, Singer & Kintsch, 2001, Graesser, Gernsbacher, & Goldman. 2003). For the purpose of this paper, two conditions were designed: an explicit condition with both a consistently maintained discourse topic and the person-specific verb modals on one hand, and a neutral condition with no discourse topic or morpho-syntactic information provided, on the other. We measured the reading tines far the target sentence containing a null pronoun and the question response times for finding an antecedent, and the accuracy rates for finding an antecedent. During the experiments each passage was presented at a tine on a computer-controlled display. Each new sentence was presented on the screen at the moment the participant pressed the button on the computer keyboard. Main findings indicate that processing is facilitated by macro-structure (topicality) in conjunction with micro-structure (morpho-syntax) in pronoun interpretation. It is speculated that global processing alone may not be able to determine which potential antecedent is to be focused unless aided by lexical information. It is argued that the results largely support the resonance-based model, but not the minimalist hypothesis.

• Journal of KIISE
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• v.44 no.10
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• pp.1026-1033
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• 2017

In this paper a Bayesian modeling and duration-based prediction method is proposed for health clinic time series data using the Hierarchical Dirichlet Process Hidden Markov Model (HDP-HMM). HDP-HMM is a Bayesian extension of HMM which can find the optimal number of health states, a number which is highly uncertain and even difficult to estimate under the context of health dynamics. Test results of HDP-HMM using simulated data and real health clinic data have shown interesting modeling behaviors and promising prediction performance over the span of up to five years. The future of health change is uncertain and its prediction is inherently difficult, but experimental results on health clinic data suggests that practical long-term prediction is possible and can be made useful if we present multiple hypotheses given dynamic contexts as defined by HMM states.