• Journal of Institute of Control, Robotics and Systems
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• v.3 no.1
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• pp.52-60
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• 1997

In genetic algorithms(GA), a crossover is performed only at one or two places of a chromosome, and the fixed probabilities of crossover and mutation have been used during the entire generation. A GA with dynamic mutation is known to be superior to GAs with static mutation in performance, but so far no efficient dynamic mutation method has been presented. Accordingly in this paper, a GA is proposed to perform a uniform crossover based on the nucleotide(NU) concept, where DNA and RNA consist of NUs and also a concrete way to vary the probabilities of crossover and mutation dynamically for every generation is proposed. The efficacy of the proposed GA is demonstrated by its application to the unimodal, multimodal and nonlinear control problems, respectively. Simulation results show that in the convergence speed to the optimal value, the proposed GA was superior to existing ones, and the performance of GAs with varying probabilities of the crossover and the mutation improved as compared to GAs with fixed probabilities of the crossover and mutation. And it also shows that the NUs function as the building blocks and so the improvement of the proposed algorithm is supported by the building block hypothesis.

• Journal of The Korean Association For Science Education
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• v.27 no.1
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• pp.93-104
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• 2007

The purpose of this study is to investigate brain activity both during the processing of a scientific hypothesis about biological phenomena and mental arithmetic using 3.0T fMRI at the KAIST. For this study, 16 healthy male subjects participated voluntarily. Each subject's functional brain images by performing a scientific hypothesis task and a mental arithmetic task for 684 seconds were measured. After the fMRI measuring, verbal reports were collected to ensure the reliability of brain image data. This data, which were found to be adequate based on the results of analyzing verbal reports, were all included in the statistical analysis. When the data were statistically analyzed using SPM2 software, the scientific hypothesis generating process was found to have independent brain network different from the mental arithmetic process. In the scientific hypothesis process, we can infer that there is the process of encoding semantic derived from the fusiform gyrus through question-situation analysis in the pre-frontal lobe. In the mental arithmetic process, the area combining pre-frontal and parietal lobes plays an important role, and the parietal lobe is considered to be involved in skillfulness. In addition, the scientific hypothesis process was found to be accompanied by scientific emotion. These results enabled the examination of the scientific hypothesis process from the cognitive neuroscience perspective, and may be used as basic materials for developing a learning program for scientific hypothesis generation. In addition, this program can be proposed as a model of scientific brain-based learning.

• Journal of The Korean Association For Science Education
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• v.20 no.1
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• pp.29-42
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• 2000

Hypothesis is defined as a single proposition proposed as a possible explanation for the occurrence of some observed phenomena. The purpose of this study was to analyze and categorize hypotheses generated by students on the cause of difference between the structures of muscles of the fishes and the terrestrial animals. A hypothesis-generating test was administered to 23 three college students who were majoring in science education. The study showed that college students generated manipulative and theoretical hypotheses as proposed explanations for the structural difference between muscles of the fishes and the terrestrial animals. Furthermore, students generated several hypotheses which were categorized by the quality of abductive process based on the degree of likeness between experienced knowledge and current phenomena. This study also discusses the implications of these findings for teaching and research in science education.

• Korean Journal of Cognitive Science
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• v.3 no.1
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• pp.79-111
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• 1991

This paper suggests a system which analyzes facial images through hypotheses generation and verification.A model knowledge on faical structures is to be represented in a hieratchical frame system and the process of hypothesis generation and verification is to be embodied through linking upper lower-level frames.This paper especially addresses the problem of how to selec an approproate knowledge at each stage of hypotheses generation and verification.

• Journal of The Korean Association For Science Education
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• v.26 no.1
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• pp.88-98
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• 2006

The purpose of this study was to analyze the process of scientists' science knowledge generation by employing four creative scientists as participants. Raw protocols were collected by an intensive interview method and then analyzed by a psychological modelling procedure. The present study showed that the process of knowledge generation divided into the processes of inductive, abductive, and deductive thinking. Furthermore, the inductive process in simple and operative observation was involved in the processes of generating a question, conjecture/prediction, designing an operational method, operation, and simple observation. Also, the abductive process had two components; question generation, and hypothesis generation which consisted of analyzing questions, searching explicans, and constructing hypothesis. Finally, the deductive process involved inventing abstract test methods, inventing abstract criteria, inventing concrete test methods, inventing concrete criteria, collecting results, and evaluating hypotheses and stating conclusions.

• Korean Journal of Cognitive Science
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• v.19 no.1
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• pp.57-74
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• 2008

This study aimed to investigate the preferential brain activations involed in the set size during random number generation (RNG). The BNG condition gave more increased activations in the anterior cingulate cortex (ACC), inferior frontal gyrus (IFG), inferior parietal lobule (IPL), and superior temporal gyrus (STG) than the simple counting condition, which was a control rendition. When the activations were compared by the small set size condition versus the large set size condition, broad areas covering tempore-occipital network, ACC, and postcentral gyrus were more highly activated in the small set size condition than in the large set size condition, while responses of areas including medial frontal gyrus, superior parietal lobule, and lingual gyrus were more increased in the large set size condition than in the small set size condition. The capacity hypothesis of working memory fails to explain the results. On the contrary, strategy selection hypothesis seems to explain the current observations properly.

• The Journal of Information Systems
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• v.23 no.4
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• pp.49-74
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• 2014

The introduction of smartphone caused the most revolutionary change in the domestic telecommunications market after the digital revolution. However, due to the saturation of the local market, it is expected to post negative growth in 2016 and the sales of national communication carriers is in stasis. Thus, the smartphone industry is starting to shift its marketing efforts to secure the silver generation who still has room for increase in the rate of smartphone usage. As the silver generation has physical limitations and differences in needs, the marketing strategy based on the smartphone utilization is not appropriate. This study suggests the new silver generation, who has high income level and similar characteristics to the younger generation, as the new customer segment for smartphone. We analyze the effects of the major variables of UTAUT on smartphone use, as well as examine how these relationships differ between the new silver and the net generation. We verified the hypotheses using a survey with 309 smartphone users. The research findings supported the hypotheses regarding the effects of performance expectancy, effort expectancy and facilitating conditions on smartphone use, but did not support the hypothesis on the effect of social influence. The result of the group comparisons showed that both generation have similar characteristics on innovativeness and cognitive absorption, but the moderating effect of age on performance expectancy, effort expectancy and use is stronger in conjunction with the new silver generation. The study results are expected to be used in establishing a marketing strategy for the new silver generation.

• Journal of Korean Elementary Science Education
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• v.26 no.2
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• pp.201-208
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• 2007

The purpose of this study was to analyze the structure and type of prospective elementary school teachers' scientific hypotheses generated on zoological tasks. The subjects were 18 prospective elementary school teachers. Four zoological hypothesis generation tasks were developed and administered to the subjects. After being presented with the zoological situations of the tasks, the subjects were asked to generate causal questions and scientific hypotheses. The scientific hypotheses were analyzed by the inductive approach. The results of this study showed that the hypotheses contained explicans and explicanda. The explicans were divided into two parts: 'what' and 'how'. In some cases, additional explanations were attached to the 'what' section. In addition, the hypotheses were classified into 9 types. The number of explicanda, the pattern of explicans, and the number of explicans were used as criteria for classification purposes. This study also discussed the implications of these findings for future directions in teaching and teaming in science education.

• Journal of Broadcast Engineering
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• v.2 no.2
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• pp.146-155
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• 1997

The new video coding standard Iv1PEG-4 is enabling content-based functionalities. It requires a prior decomposition of sequences into video object planes (VOP's) so that each VOP represents moving objets. This paper addresses an image segmentation method for separating moving objects from still background (non-moving area) in video sequences using a statistical hypothesis test. In the proposed method. three consecutive image frames are exploited and a hypothesis testing is performed by comparing two means from two consecutive difference images. which results in a T-test. This hypothesis test yields a change detection mask that indicates moving areas (foreground) and non-moving areas (background), Moreover. an effective method for extracting

• BMB Reports
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• v.48 no.1
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• pp.13-18
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• 2015

Alzheimer's disease severely compromises cognitive function. One of the mechanisms to explain the pathology of Alzheimer's disease has been the hypotheses of amyloid-pore/channel formation by complex $A{\beta}$-aggregates. Clinical studies suggested the moderate alcohol consumption can reduces probability developing neurodegenerative pathologies. A recent report explored the ability of ethanol to disrupt the generation of complex $A{\beta}$ in vitro and reduce the toxicity in two cell lines. Molecular dynamics simulations were applied to understand how ethanol blocks the aggregation of amyloid. On the other hand, the in silico modeling showed ethanol effect over the dynamics assembling for complex $A{\beta}$-aggregates mediated by break the hydrosaline bridges between Asp 23 and Lys 28, was are key element for amyloid dimerization. The amyloid pore/ channel hypothesis has been explored only in neuronal models, however recently experiments suggested the frog oocytes such an excellent model to explore the mechanism of the amyloid pore/channel hypothesis. So, the used of frog oocytes to explored the mechanism of amyloid aggregates is new, mainly for amyloid/pore hypothesis. Therefore, this experimental model is a powerful tool to explore the mechanism implicates in the Alzheimer's disease pathology and also suggests a model to prevent the Alzheimer's disease pathology.