• Broadcasting and Media Magazine
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• v.11 no.1
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• pp.78-85
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• 2006

Cognitive radio is a paradigm for wireless communication in which either network of wireless node itself changes particular transmission or reception parameters to execute its tasks efficiently without interfering with the licensed users. This paper represents a performance of the cognitive radio technology on dual polarized MIMO system using six-port receiver. Six-port technology is well known direct conversion receiver. In this paper, a six-port phase discriminator based polarization signal separation is shown. That is, the SER(Symbol Error Rate) performance is improved using polarization separator and simple receiver architecture is proposed applying six-port receiver. The six-port technology has priority to adapt changeable frequency system and variable environments for cognitive radio. In general, dual polarized MIMO system has good capacity and quality using polarization separator [1].

• Journal of the Ergonomics Society of Korea
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• v.35 no.4
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• pp.225-235
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• 2016

Objective: The aim of this study is to model all levels of situation awareness (SA), which would be able to predict situation awareness quantitatively. Background: When measuring situation awareness, directly measuring SA methods such as SAGAT and SART have been utilized. Several approaches (cognitive modeling approaches) were introduced to model SA but level 3 SA was not completed. For real-life situation, however, it is necessary to detect the problematic level of SA rather than overall SA. Therefore, we proposed a new model of all levels of SA in this study. Method: In order to model all levels of SA, this study chose factors in ACT-R architecture through literature review. ATC (Air Traffic Control)-related simulation task was video-taped to analyze human behaviors in order to model all levels of SA including level 3. Results: As a result, regression analyses show that cognitive activities (neural activations) represented for all levels of SA were highly correlated with SAGAT. Conclusion: In conclusion, neural activations in ACT-R could be proved to be effective to model all levels of SA. Application: Our SA model could be used to predict all levels of SA quantitatively without directly measuring the SA of operators.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.7
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• pp.2960-2976
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• 2018

The limited storage and computing capacity hinder the development of cognitive radio ad hoc networks (CRAHNs). To solve the problem, a new paradigm of cloud-based CRAHN has been proposed, in which a CRAHN will make use of the computation and storage resources of the cloud. This paper envisions an integrated CRAHN-cloud network architecture. In this architecture, some cognitive radio users (CUs) who satisfy the required metrics could perform as mobile gateway candidates to connect other ordinary CUs with the cloud. These mobile gateway candidates are dynamically clustered according to different related metrics. Cluster head and time-to-live value are determined in each cluster. In this paper, the gateway advertisement and discovery issues are first addressed to propose a hybrid gateway discovery mechanism. After that, a QoS-based gateway selection algorithm is proposed for each CU to select the optimal gateway. Simulations are carried out to evaluate the performance of the overall scheme, which incorporates the proposed clustering and gateway selection algorithms. The results show that the proposed scheme can achieve about 11% higher average throughput, 10% lower end-to-end delay, and 8% lower packet drop fractions compared with the existing scheme.

• Korean Institute of Interior Design Journal
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• v.15 no.4 s.57
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• pp.138-146
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• 2006

Main elements in definition of space value were physical, formal, and reasonable characteristics in the past. Howener recently, definition of space value is changing by being advanced about study concerned with human's cognition and thinking way in definition and analysis of space. As you see, cognitive psychologists have emphasized the importance of human's cognitive structure and process and studied diverse aspects of human's thinking ; consciousness, perception, memory, image, language, decision-making, inference, and so on. Therefore main elements in definition of space value are five-dimensional, psychological, symbolic, mental, emotional characteristics above physical, formal, and reasonable characteristics. As mentioned above, the conversion of thinking focused on reason to thinking focused on human's spirit and emotion is achieved in contemporary architecture and 'human's experience' in space becomes a very important factor. For that reason, the purpose of this study is consideration of human's cognitive process in space by conversion of thinking and gives a definition about experience. And, I would like to define 'experience design' whose main attribute is experience in space and establish theoretical basis of experience design through theoretical researches about experience. This study on experience design that induces users to participate in space and stimulate human's spirit is a important point in definition of space value not only contemporary interior architecture but also prospective generation.

• Korean Journal of Cognitive Science
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• v.5 no.2
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• pp.47-73
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• 1994

In this paper, a blackboard-based road image understanding system is implemented. The 7 useful information which organized by the hierarchical manner are stored in the blackboard system. The 6 Knowledge source modules and the blackboard make the communications under the supervision of the control module. For a scene, each hypothesis is generated and then verified for every meaningful object. On the simulation results, the correct recognition ratio can be reached out 90%. It shows that the extraction of road information for the autonomous navigation can be obtained using the blackboard architecture.

• Proceedings of the Korea Society of Design Studies Conference
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• 2003.05a
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• pp.140-141
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• 2003

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.4 s.111
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• pp.45-70
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• 2005

The purpose of this study is to overview foreign trends in the study of the landscape ecology through new framework of landscape ecological studies and to suggest possibility and limitation of introduction of landscape ecology studies in Korea. Because of historical reasons rooted in different disciplines, landscape ecology of the present time is not unified at all. Therefore, landscape ecology should be understood in an integrative manner accommodating different views and various aspects of landscape(NOOS, GEOS, BIOS). Facing the increasing environmental problems and the goal of sustainable landscape, the principle of a holistic approach complementarity and transdisciplinarity outlined in this paper (esp. connection physical-materials and cognitive system) might help to understand the characteristics of landscapes and landscape ecology. Important steps towards this direction are the landscape survey, diagnosis, the identification of landscape functions, the development of landscape evaluation models and landscape planning system. Recently there have been a few landscape ecological researches in Korea, which tells there have been strong needs to solve practical landscape problems caused by the rapid socioeconomic growth for several decades. However, almost of this studies are focused on cognitive and visual aspects of landscapes defined boundaries of disciplines. But for more holistic approach complementarity and transdisciplinarity in landscape ecological studies, many other aspects such as the consideration of geoecological and bioecologocal variables, preperation of ecological basic data(mapping) and the development of landscape planning as a tool for practical application should be integrated into the whole landscape system.

• Journal of Information Processing Systems
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• v.8 no.1
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• pp.133-144
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• 2012

In order to make cognitive radio systems a practical technology to be deployed in real-world scenarios, the core Software Defined Radio (SDR) systems must meet the stringent requirements of the target application, especially in terms of performance and energy consumption for mobile platforms. In this paper we present a feasibility study of hardware acceleration as an energy-efficient implementation for SDR. We identified the amplifier function from the Software Communication Architecture (SCA) for hardware acceleration since it is one of the functions called for most frequently and it requires intensive floating-point computation. Then, we used the Virtex5 Field-Programmable Gate Array (FPGA) to perform a comparison between compiler floating-point support and the on-chip floating-point support. By enabling the on-chip floating-point unit (FPU), we obtained as high as a 2X speedup and 50% of the overall energy reduction. We achieved this with an increase of the power consumption by no more than 0.68%. This demonstrates the feasibility of the proposed approach.

• Journal of Digital Convergence
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• v.14 no.4
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• pp.425-435
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• 2016

This paper has the aim to track down the viewers' cognitive emotion of how they are interacting with the story of Shakespeare in Love. Human minds have cognitive and emotional flows while plots, characters, and action-ideas are intertwined in the story of the film. This paper especially focused on the analysis of characters' networks with four statistical data pictures in order to schematize the storytelling architecture on how and why Shakespeare has strongly motivated to write a great star-crossed love play, Romeo and Juliet in his very young age. This paper examines that Shakespeare's subject of desire is to accomplish both a true love and a sincere play which can make the nature of love true. The desire of subject is always slipped aside into scattering with "object a." In the film of Shakespeare in Love, the "object a" is a writing process and has a product of Romeo and Juliet as well.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.4
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• pp.1845-1865
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• 2019

Current Internet is designed by lots of service providers with different objects and policies which make the direct deployment of radically new architecture and protocols on Internet nearly impossible without reaching a consensus among almost all of them. Network virtualization is proposed to fend off this ossification of Internet architecture and add diversity to the future Internet. As an important part of network virtualization, virtual network embedding (VNE) problem has received more and more attention. In order to solve the problems of large embedding cost, low acceptance ratio (AR) and environmental adaptability in VNE algorithms, cognitive method is introduced to improve the adaptability to the changing environment and a cognitive virtual network embedding algorithm based on weighted relative entropy (WRE-CVNE) is proposed in this paper. At first, the weighted relative entropy (WRE) method is proposed to select the suitable substrate nodes and paths in VNE. In WRE method, the ranking indicators and their weighting coefficients are selected to calculate the node importance and path importance. It is the basic of the WRE-CVNE. In virtual node embedding stage, the WRE method and breadth first search (BFS) algorithm are both used, and the node proximity is introduced into substrate node ranking to achieve the joint topology awareness. Finally, in virtual link embedding stage, the CPU resource balance degree, bandwidth resource balance degree and path hop counts are taken into account. The path importance is calculated based on the WRE method and the suitable substrate path is selected to reduce the resource fragmentation. Simulation results show that the proposed algorithm can significantly improve AR and the long-term average revenue to cost ratio (LTAR/CR) by adjusting the weighting coefficients in VNE stage according to the network environment. We also analyze the impact of weighting coefficient on the performance of the WRE-CVNE. In addition, the adaptability of the WRE-CVNE is researched in three different scenarios and the effectiveness and efficiency of the WRE-CVNE are demonstrated.