• Journal of Environmental Science International
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• v.14 no.1
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• pp.1-8
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• 2005

CFD code are used for numerically testing a new concept of large space air control system. A workshop with air-conditioners products lines and air-conditioned by several floor type air-containers is tested. The whole room air distribution is controlled by boosters installed in a middle height horizontal plane. First, calculated results are compared with measured data to confirm the validity and applicability of the prediction method. Next, the method is applied to case studies heating seasons. Results under some operating conditions show effectiveness in avoid the temperature stratification in winter.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.4
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• pp.49-55
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• 2010

In this paper, we propose the symbol decision method considering the non-uniformity in color space and analyze the BER performance of modulation scheme based on color space, comparing with the conventional WDM scheme based on light intensity. Through numerical simulation, we show the BER performance superiority under the condition of AWGN and common mode noise.

• Journal of the Korean housing association
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• v.20 no.5
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• pp.85-92
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• 2009

In the coming 21st centuries, words of development of information communication technology among the key words being emerged as an important concern have been talked about frequently and ubiquitous environment that helps human living being networked with humans, objects and environments has been rapidly progressed, influencing significantly over the various fields as well as architectural area. And eventually in this architectural area, the space that is desired to be shown to and experienced by the people could be found in the creation of a space in a new form that has not been existed in this world by utilizing the information communication technology. The future housing delicately add using technology and AR system which is an essential element. The purpose of this study is to production and using each element and develop one-step advanced the hybrid system space. We have to select the best way of the construction future housing.

• Journal of Communications and Networks
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• v.13 no.3
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• pp.257-265
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• 2011

In this paper, a cooperative relaying protocol called soft-decision-and-forward (SDF) with multiple antennas in each node is introduced. SDF protocol exploits the soft decision source symbol values from the received signal at the relay node. For orthogonal transmission (OT), orthogonal codes including Alamouti code are used and for non-orthogonal transmission (NT), distributed space-time codes are designed by using a quasi-orthogonal space-time block code. The optimal maximum likelihood (ML) decoders for the proposed protocol with low decoding complexity are proposed. For OT, the ML decoders are derived as symbolwise decoders while for NT, the ML decoders are derived as pairwise decoders. It can be seen through simulations that SDF protocol outperforms AF protocol for both OT and NT.

• Journal of the Korea Society of Computer and Information
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• v.10 no.1 s.33
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• pp.149-156
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• 2005

In the actuality that the various services are provided in connection with the network of internet by activating the communication using Propagation, the importance of the feature point and chase of an object is greatly raised to increase the quality of the detection and tracking of the communication service. This paper is to detect the shadow space by using Snakes Algorithms and Present a system's base which tracts the route from start to target points in the detected shadow space as a study for the detection and tracking the shadow space which does not reach the propagation.

• Journal of Communications and Networks
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• v.12 no.3
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• pp.240-245
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• 2010

Jacket matrices, motivated by the complex Hadamard matrix, have played important roles in signal processing, communications, image compression, cryptography, etc. In this paper, we suggest a novel approach to design a simple class of space-time block codes (STBCs) to reduce its peak-to-average power ratio. The proposed code provides coding gain due to the characteristics of the complex Hadamard matrix, which is a special case of Jacket matrices. Also, it can achieve full rate and full diversity with the simple decoding. Simulations show the good performance of the proposed codes in terms of symbol error rate. For generality, a kind of quasi-orthogonal STBC may be similarly designed with the improved performance.

• Journal of information and communication convergence engineering
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• v.10 no.3
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• pp.269-275
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• 2012

In this paper, we proposed a novel location estimation algorithm based on the concept of space-time signature matching in a moving target environment. In contrast to previous fingerprint-based approaches that rely on received signal strength (RSS) information only, the proposed algorithm uses angle, delay, and RSS information from the received signal to form a signature, which in turn is utilized for location estimation. We evaluated the performance of the proposed algorithm in terms of the average probability of error and the average error distance as a function of target movement. Simulation results confirmed the effectiveness of the proposed algorithm for location estimation even in moving target environment.

• Journal of information and communication convergence engineering
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• v.2 no.2
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• pp.61-66
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• 2004

This paper presents a way to maximize transmission efficiency and reception ability through transmission diversity technology, which can be adapted to wireless multimedia Wireless LAN system. The presented method is a comparative analysis between a case where parameter a for time average is 0.3.1 with consideration of channel presumption with two types of rms delayed spread, which is 50nsec. 150nsec, for the performance analysis of STTC (Space-Time Trellis Code) adopting time-space ciphering method appropriate for MIMO channel, and performance in the case where presumed channel value from long training column section is applied to according frame in a single frame. The result showed that BER brought SNR improvement of l.0dB in $10^{-3}$ when a was 0.3 than adopting only the long training column, and showed increase of general performance improvement for the sake of time average rather than the case without.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.7
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• pp.7-14
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• 2004

In an upcoming ubiquitous era, humankind will live in a ubiquitous space, where everything is connected through communication network. In this ubiquitous space, a ubiquitous robot, which can be used by anyone for any service through any device and any network at anytime and anywhere in a u-space, is expected to be required to serve seamless and context-aware services to humankind. In this paper, we introduce the ubiquitous robot, and define three components of the ubiquitous robot. The first one is "SoBot" which can be connected through the network in anywhere with environment recognition function and communication ability with human. The second one is "EmBot" which is embedded into environments and mobile robots and has localization and certification function with sensor fusion. The last one is "Mobile Robot" which serves overall physical services. This paper also introduces KAIST ITRC-Intelligent Robot Research Center that pursues the implementation of the ubiquitous robot.

• Annual Conference of KIPS
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• 2024.05a
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• pp.133-136
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• 2024

전 산업에서 초고속 저지연 데이터 서비스 수요가 증가하면서 저지연 트래픽 (low latency traffic, LLT) 처리 중요성이 커지고 있다. 기존 연구들은 LLT 에 우선순위를 부여하여 먼저 처리하는 프리 엠프션 기법을 제안했으나 제어 오버헤드가 증가하거나 non-LLT 트래픽 성능을 열화하는 문제를 해결할 수 없었다. 본 논문에서는 이러한 문제를 해결하기 위해 종래에 사용하지 않았던 짧은 인터프레임 스페이스 (Short Interframe Space, SIFS)를 LLT 에 활용하는 새로운 전송 기법을 제안한다. 본 논문에서는 수치 분석을 통해 제안하는 인터프레임 스페이스 통신 (Interframe Space Communication, ISC)이 종래의 전송 방법 대비 스루풋을 평균 50% 개선하고 지연도를 98% 개선할 수 있음을 보였다.