• Proceedings of the IEEK Conference
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• 2000.11a
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• pp.149-152
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• 2000

In this paper, the reverse link performance of an imperfect power controlled DS/CDMA cellular system that uses a base station array antenna which can effectively remove the multiple access interference is analyzed considering both beam forming algorithm and power control error in shadowing. The blocking probability of the DS/CDMA cellular system based on array parameters, Eb/No and statistics of interference is derived, and then the system capacity corresponding to a certain blocking probability is calculated. On the assumption that the blocking probability is set 1 ％, the system capacity using MCGM algorithm with 12 antenna arrays is increased about 59 % than that using 8 antenna arrays when power control error is 2.5 ㏈.

• Proceedings of the IEEK Conference
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• 2004.06b
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• pp.411-414
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• 2004

This paper introduces a modulation method for digital wireless communication based on general DS-QPSK. The design and fabrication is for home networking application to a typical RF transmitter with DS-QPSK modulator. This modulator implemented using VHDL hardware programming language, the fabrication of IC chip $5{\times}5 mm^2$ was carried by 27th IDEC MPW(Multi Project Wafer) process in 0.35${\mu}m$ rule at Samsung Inc. This paper presented the important of this technology for the future application in wireless sensor. This module can be efficient usage for home network to transmit the RF wireless sensor system.

• Journal of Microbiology and Biotechnology
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• v.27 no.4
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• pp.834-837
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• 2017

A distinct double-stranded RNA (dsRNA) cryptic virus, named spinach cryptic virus 1 (SpCV1), was identified from spinach transcriptome datasets. The SpCV1 genome has two dsRNA genome segments. The larger dsRNA1 has an open reading frame for a conserved RNA-dependent RNA polymerase (RdRp). The smaller dsRNA2 encodes a putative coat protein (CP). The sequence identity of SpCV1 RdRp and CP to the closest cryptic virus is 81% and 60%, respectively. Phylogenetic analysis indicates that SpCV1 is a novel member of the genus Alphapartitivirus (family Partitiviridae).

• Asia pacific journal of information systems
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• v.7 no.3
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• pp.1-21
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• 1997

본 논문에서는 인터넷 기반의 새로운 DSS 개념인 인터넷 DSS 개념적인 설계를 제안한다. 제안하는 인터넷 DSS는 인터넷 환경에서 효과적으로 구동될 수 있도록 지능형 에이전트(Intelligent Agent)를 주요 구성모듈로 하고 있으며, 네트웍 통신층, 문제해결층, 그리고 사용자 인터페이스층 등 다층구조를 갖고 있다. 인터넷 DSS 가능성을 구체적으로 보여주기 위하여 기업내에서 전략적으로 가장 첨예한 대립관계를 보이고 있는 마케팅 부서와 생산관리 부서간의 전략적 통합문제에 적용하여 그 의미를 분석하였다. 이는 최근 기업경영이 글로벌화 되어가면서 마케팅과 생산기능이 지리적으로 떨어져서 운영되는 것이 일반화되어 가고 있기 때문에 기존의 DSS보다는 인터넷 DSS가 이러한 경우에 훨씬 적용가능성이 높기 때문이다. 본 논문에서는 인터넷 DSS를 구성하는 모듈중에서 주로 모형에이전트의 모형결합 메카니즘을 중심으로 설명하였고 결론부분에서 향후 연구방향을 제시하였다.

• Proceedings of the IEEK Conference
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• 2001.09a
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• pp.579-582
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• 2001

The performance of a coherent rake receiver of DS-CDMA systems is significantly affected by the accuracy of channel estimation. The performance of the channel estimator can be improved by employing a channel estimation filter (CEF) whose impulse response is adjusted according to the channel condition. In this paper, we consider the design of an adaptive channel estimator for DS-CDMA systems with a pilot channel. The proposed channel estimator estimates the channel condition, which can be performed without haying exact a priori information on the operating condition. The estimated channel condition adjusts the impulse response of the CEF. Numerical results show that the use of the proposed channel estimator can provide BER performance quite robust to a wide range of channel condition.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.237-240
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• 1998

BISDN 망 구축을 위한 ATM 교환기는 고속의 스위치 망을 통해 사용자들의 고속 정보를 교환 할 수 있는 경로를 제공하고 있으며, 기존 통신망들과의 연동을 통해 다양한 서비스를 제공하기 위하여 여러 가지 가입자 정합장치의 수용이 요구되고 있다. 현재 국내에서 개발되어 시험중인 HANbit ACE ATM 교환기는 DS-1, DS-1E, DS-3 및 STM-1급의 가입자 정합 장치를 제공하며, 중계선 정합 장치로는 DS-3 및 STM-1 급을 지원한다. 이러한 구조에서 사용자 QOS 를 만족시키며 네트워크 비용을 최소화 시키는데 많은 어려움이 따른다. 즉 다양한 정합장치와 다단 스위치 구조하에서 다양한 트래픽 특성을 갖는 호/연결에 대한 효과적인 호 수락 제어 기능이 필수적으로 요구된다. 본 고에서는 다양한 정합 장치와 3단 스위치 구조를 갖는 HANbit ACE ATM 교환기를 살펴보고, 다양한 트래픽 수용을 위한 트래픽제어 요구사항을 알아보며, 이와 같은 특성을 해결하고자 실현된 호/연결 수락 제어 기능에 대해 고찰한다.

• Journal of the Korean Wood Science and Technology
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• v.24 no.4
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• pp.82-86
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• 1996

This study was performed to elucidate the effect of degree of substitution and degree of polymerization of CMC on the rheological characteristics of coating color which is consisted of calcium carbonate as pigment. The results were as follows: 1. It appeared that DP of CMC rather DS has an effect on the low shear viscosity of coating color. 2. According as shear rate increased, the effect of DP and DS on high shear viscosity of coating color decreased. 3. According to increasing DS and DP, the water retention of coating color increased.

• Journal of Advanced Navigation Technology
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• v.13 no.4
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• pp.544-550
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• 2009

In this paper, we proposed the radio wave propagation characteristics of the next-generation ultrafast wireless communication system in millimeter-wave fading channel. For considering doppler shift and Rayleigh fading simultaneously, the fading simulator of Jakes model implemented and analyzed the performance of the next-generation wireless communication system. In addition, the error rate characteristics of DS-CDMA system analyzed in the millimeter-wave fading channel and the system performance improved by coding technique and diversity technique.

• Journal of Communications and Networks
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• v.8 no.2
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• pp.220-227
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• 2006

In this paper, we present a novel approach to analyze the throughput of direct-sequence spread spectrum multiple access (DS/SSMA) unslotted ALOHA system. In the unslotted system, the departure rate of interfering transmissions is proportional to the number of current interferers that can be regarded as the system state. In order to model this state-dependency, we introduce a two-dimensional state transition model that describes the state transition of the system. This model provides a more rigorous analysis tool for the DS/SSMA unslotted ALOHA systems with both fixed and variable packet lengths. Numerical results reveal that this analysis yields an accurate system performance that coincides with the simulation results. Throughout the analysis we have discovered that the state-dependency of the departure rate causes interference averaging effect in the unslotted system and that this effect yields a higher throughput for the unslotted system than for the slotted system when supported by a strong channel coding.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.49-52
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• 2001

An experimental study was conducted to test the feasibility of degradative solidification/stabilization (DS/S) process in treating tetrachloroethylene (PCE) in solid phase systems. The Fe(II)-based ds/s process successfully treated PCE in a soil at the reaction rates that would not allow significant release of the contaminant in the environment. A leach model was also developed that could describe the relative importance of leaching and degradation in ds/s. The first and second Damkohler numbers and dimensionless time were important parameters that determined leaching precesses in wastes treated by ds/s.