• Spatial Information Research
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• v.18 no.1
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• pp.101-107
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• 2010

Context-aware technologies have become the one of core technologies for intelligent urban geospatial services in ubiquitous computing environment. To provide context-aware intelligent services, various technologies including for context-aware modelling, context-aware sensing and context-aware service middleware are required. Among them, especially, ontologies are very useful for modelling, interpreting and reasoning context informations across various domains. In this research, the recent trends of context-awareness technologies and ontologies are reviewed to build a conceptual architecture for intelligent urban geospatial services. Considering it, the strategies of intelligent urban geospatial services are proposed.

• Journal of Broadcast Engineering
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• v.18 no.1
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• pp.1-9
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• 2013

Accuracy of the 3-D model is essential in model-based camera tracking. However, 3-D object modeling requires dedicated and complicated procedures for precise modeling without any errors. Even if a 3-D model contains a certain level of errors, on the other hand, the tracking errors cause by the modeling errors can be different from its perceptual errors; thus, it is an important aspect that the camera tracking can be successful without precise 3-D modeling if the modeling errors are within the user's permissible range. In this paper, we analyze the tolerance of 3-D object modeling errors by comparing computational matching errors with perceptual matching errors through user evaluations, and also discuss permissible ranges of 3-D object modeling errors.

• Archives of design research
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• v.20 no.1 s.69
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• pp.203-218
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• 2007

Does CAD technology have a possibility to promote new logics of design thinking and form-creation? Starting with such a question, this study inquires into soical constructions of linear perspective and CAD programs. Using a concept of the modelling interface as an analytical frame, this study discusses; 1) a historical process in which the linear perspective, as a drawing-oriented modelling interface, had permeated its geometrical principles into the artificial environment and justified them in a dimension of the aesthetic discourse, 2) technological contexts in which computer-based modelling interfaces such CAD programs were developed and separated from the tradition of the linear perspective, with the introduction of new kinds of modelling algorithms and graphic user interfaces.

• Journal of Educational Research in Mathematics
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• v.27 no.2
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• pp.313-328
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• 2017

This study aims to identify prospective elementary school teachers' perception of mathematical modeling in elementary class. Forty elementary school teachers participated in this study. Each teacher analysed the previous case studies about mathematical modeling in elementary class, developed a hypothetical learning trajectory, applied the hypothetical learning trajectory to his/her class, reflected students' learning and his/her teaching, and made reflective journals. These journals contained teachers' perception of mathematical modeling and the difficulties that teachers experienced in teaching mathematics as mathematical modeling. These journals were analyzed to identify teachers' perception of mathematical modeling in elementary class. This study shows that teachers have common features of mathematical modeling but their perspectives are little bit different, are classified into four kinds. And the difficulties that teachers experienced in teaching mathematics as mathematical modeling are classified into 5 categories; Task, Students' cognitive demand, Teacher' monitering, All students' participation, and Classroom culture. At last, suggestions for mathematical modeling in elementary class are done according to the result of this study.

• Proceedings of the Korean Information Science Society Conference
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• 2006.10b
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• pp.111-115
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• 2006

가상환경 탐색 항해 기법을 설계했다 3차원 가상환경은 입체적 시각 정보를 통해서 사용자가 가상환경을 현실로 받아들이고 마치 현장에 위치해 있는 것과 같은 감각을 느끼게 한다. 이러한 감각에 의지해서 사용자는 진지하고도 적극적으로 가상환경에 참여할 수 있다. 3차원 가상환경이 지닌 이러한 장점은 오락프로그램의 흥미 증진, 교육 및 군사훈련의 효과 향상, 의료분야의 신기술개발 등 다양한 분야에서 활용되고 있다. 그러나 3차원 가상환경은 현실 세계에 비해 빈약한 공간 인지 정보로 인해 자신의 위치를 인지하기 못하거나 원하는 목표물을 찾는데 어려움이 있다. 따라서 본 연구 에서는 가상환경을 구성하는 물리적인 정보와 가상환경의 외부 정보를 토픽맵(Topic Map)에서 제시 하는 기법을 사용하여 공간 인지 지식을 모델링 하였고, 현실세계에서 인간의 두뇌에서 이루어 지는 과정과 유사하게 3차원 가상환경 내에서도 길찾기기 가능하도록 인지맵(cognitive map)기법을 적용하여 처음 가상환경에 방문한 사용자라도 쉽게 목표물에 접근할 수 있는 개인화된 투어가이드 기법을 개발 하였다.

• Journal of Broadcast Engineering
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• v.17 no.2
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• pp.223-236
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• 2012

We develop a video processing method that allows the more advanced human perception oriented video coding. The proposed method necessarily reflects all influences by the rate-distortion based optimization and the human visual perception that is affected by the visual saliency, the limited space-time resolution and the regional moving history. For reflecting the human perceptual effects, we devise an online moving pattern classifier using the Hedge algorithm. Then, we embed the existing visual saliency into the proposed moving patterns so as to establish a human visual perception model. In order to realize the proposed human visual perception model, we extend the conventional foveation filtering method. Compared to the conventional foveation filter only smoothing less stimulus video signals, the developed foveation filter can locally smooth and enhance signals according to the human visual perception without causing any artifacts. Due to signal enhancement, the developed foveation filter more efficiently transfers the bandwidth saved at smoothed signals to the enhanced signals. Performance evaluation verifies that the proposed video processing method satisfies the overall video quality, while improving the perceptual quality by 12%~44%.

• School Mathematics
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• v.6 no.4
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• pp.389-409
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• 2004

This article presents a case study in which three middle school students developed models in modeling activity using a tool. We research the interaction of model development process and the activities operating a tool in the modeling. And we investigate whether students are able to create generalizable model, after a tool mediates students' thought process and students internalize the perceptive activity operating a tool. The analysis of our case study led to three results. First, as students were able to integrate perceptive activity operating a tool and cognitive activity, they reasoned about the relationships among changing quantities and developed the model. Second, students corrected and refined developed models with reflecting the perceptive activity operating a tool. Third, as students internalized perceptive activity, students were able to create generalizable model, which is a graph of height as a function of the amount of water that's in the beaker.

• KIISE Transactions on Computing Practices
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• v.20 no.12
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• pp.700-705
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• 2014

An anagram is a form of word play to find a new word from a set of given alphabet letters. Good human anagram solvers use the strategy of bigrams. They explore a constraint satisfaction network in parallel and answers consequently pop out quickly. In this paper, we propose a molecular computational algorithm using the same process as this. We encoded letters into DNA sequences and made bigrams and then words by connecting the letter sequences. From letters and bigrams, we performed DNA hybridization, ligation, gel electrophoresis and finally, extraction and separation to extract bigrams. From the matched bigrams and words, we performed the four molecular operations again to distinguish between right and wrong results. Experimental results show that our molecular computer can identify cor rect answers and incorrect answers. Our work shows a new possibility for modeling the cognitive and parallel thinking process of a human.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.3
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• pp.51-58
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• 2010

Since Augmented Reality (AR) enables users to experience computer-generated content embedded in real environments, AR agents can be visualized among physical objects in the environments where the users exist, and directly interact with them in real-time. We model perceptual attention for autonomous agents in AR environments where virtual and physical objects coexist. Since such AR agents must adaptively perceive and attend to surrounded objects relevant to their goals, our model allows the agents to determine currently visible objects from the description of what virtual and physical objects are configured in the camera's viewing area. A degree of attention is assigned to each perceived object based on its relevance to achieve agents' goals. The agents can focus on a reduced set of perceived objects with respect to the estimated degree of attention. To demonstrate the effectiveness of our approach, we implemented an animated character that was overlaid over a miniature version of campus and that attended to buildings relevant to their goals. Experiments showed that our model could reduce the character's perceptual loads even when surroundings change.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.1
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• pp.85-89
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• 2010

Most images are composed as union of the various objects which can describe meaning respectively. Unlike human perception, The general computer systems used for image processing analyze images based on low level features like color, texture and shape. The semantic gap between low level image features and the richness of user semantic knowledges can bring about unsatisfactory classification results from user expectation. In order to deal with this problem, we propose a semantic cue based image classification method using salient points from object of interest. Salient points are used to extract low level features from images and to link high level semantic concepts, and they represent distinct semantic information. The proposed algorithm can reduce semantic gap using salient points modeling which are used for image classification like human perception. and also it can improve classification accuracy of natural images according to their semantic concept relative to certain object information by using salient points. The experimental result shows both a high efficiency of the proposed methods and a good performance.