• Title/Summary/Keyword: Ds

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Characteristics of Waterlevel Fluctuation in Riverside Alluvium of Daesan-myeon, Changwon City (창원시 대산면 강변충적층의 지하수위 변동 특성)

  • Cheong, Jae-Yeol;Hamm, Se-Yeong;Kim, Hyoun-Su;Son, Keon-Tae;Cha, Yong-Hoon;Jang, Seong;Baek, Keon-Ha
    • The Journal of Engineering Geology
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    • v.13 no.4
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    • pp.457-474
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    • 2003
  • This study aims to elucidate characteristics of groundwater level fluctuation at riverbank filtration sites in Daesan-myeon, Changwon City. Groundwater level fluctuation, river water level change and stream-aquifer interaction are very important to estimate optimal discharge rate of the pumping well. Water level contours from February 2003 to October 2003 show normal decreasing trend toward the Nakdong river with the hydraulic gradient of 0.008. However, flow reversion occurs when groundwater is discharged at the pumping wells or rise of the Nakdong river by rainfall. The fluctuation of the Nakdong river ranges 0 - 10 m msl. Autocorrelation analysis was conducted to the groundwater levels measured on the six monitoring wells (DS1, DS2, DS3, DS4, DS6 and DS7). The analyzed waterlevel data can be grouped into three: group 1 (DS1 and DS3) represents strong linearity and long memory effect, group 2 (DS1 and DS6) intermediate linearity and memory, and group 3 (DS4 and DS7) weak linearity and memory. Waterlevels of group 1 wells are relatively closely related to the change of river-water level. Those of group 2 wells are largely affected by the pumping and the river-water level, and those of group 3 wells are strongly linked to pumping.

Performance Improvement of Multi-Carrier DS-CDMA System using Hybrid SC/MRC-Lc/L Diversity Received Technique (Multi-Carrier: DS-CDMA 시스템에서의 하이브리드 SC/MRC-Lc/L 다이버시티 수신 기법을 이용한 성능 개선)

  • Kim, Young-Chul
    • Journal of Digital Contents Society
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    • v.7 no.4
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    • pp.279-285
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    • 2006
  • In this paper, we have considered the performance improvement of Multi-Carrier DS-CDMA system using hybrid SC/MRC-Lc/L diversity receiving technique over multipath fading environment and compared with that of a Wideband DS-CDMA system. In the result, the PBI has caused a performance deterioration over partial bandwidth in Multi-Carrier DS-CDMA system. Also, Multi-Carrier DS-CDMA system using Hybrid SC/MRC-Lc/L diversity received can determined the complexity and the performance vs the expenses for the system that select the number of input branches.

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Molecular Biological Characteristics of Ustilago maydis Virus Isolated in Korea

  • Won, Yie-Se;Choi, Hyoung-Tae
    • Korean Journal of Microbiology
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    • v.30 no.3
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    • pp.177-180
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    • 1992
  • Among 120 U. maydis strains isolated in Korea 14 different strains containing specific viral dsRNA segments were analyzed for the distribution of dsRNA and the production of toxin protein. Several distinctive dsRNA patterns were identified, 9 cases of P type with typical H, M and L ds RNA and one case of non-P-type, the frequency of a specific isolate was decreased with increasing number of dsRNA segments. The presence of dsRNA had no effect on the cultural or morphological phenotype of the host. Two isolates containing P type dsRNA segments appeared to produce toxin protein (killer strains) which inhibited the growth of 4 isolates (sensitive strain) with different susceptibility. Two killer strains contain unique M dsRNA segment which may code for toxin protein. However, the presence of toxin-sensitive strains among dsRNA-free isolates was similar to that of ds RNA containing strains.

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Performance Improvement of MFSK-MDPSK/DS-CDMA System Employing MRC Diversity Techniques and Convolution Coding Techniques in Nakagami Fading Environment (나카가미 페이딩 환경하에서 MRC 다이버시티기법과 컨벌루션 부호화 기법을 채용한 MFSK-MDPSK/DS-CDMA 시스템의 성능 개선)

  • 박형호;김영철;강희조;이권현;조성준
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.8 no.2
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    • pp.173-184
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    • 1997
  • In most DS-CDMA systems, the modulation scheme used is a simple one. In this paper, the error performance of DS-CDMA system employing a MFSK-MDPSK combined moulation techniques in adopting MRC diversity reception and convolution coding technique are evaluated. The obtained result show that the error performance of MFSK-MDPSK/DS-CDMA system in Nakagami fading environments is improved by increasing the number of diversity branch and coding gain. Also the power efficiency and bandwidth efficiency combined system in MFSK/ DS-CDMA, MDPSK/DS-CDMA are better than conventional MFSK-MDPSK/DS-CDMA systems.

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식물의 물질생산과 수분스트레스

  • 김준호
    • Proceedings of the Botanical Society of Korea Conference
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    • 1985.08b
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    • pp.59-71
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    • 1985
  • In rice, limited efforts have been made to identify genes by the use of insertional mutagens, especially heterologous transposons such as the maize Ac/Ds. We constructed Ac and gene trap Ds vectors and introduced them into the rice genome by Agrobacterium-mediated transformation. In this report, rice plants that contained single and simple insertions of T-DNA were analyzed in order to evaluate the gene-tagging efficiency. The 3'end of Ds was examined for putative splicing donor sites. As observed in maize, three splice donor sites were identified at the 3'end of the Ds in rice. Nearly 80% of Ds elements wered excised from the original T-DNA sites, when Ac cDNA was expressed under a CaMV 35S promoter. Repetitive ratoon culturing was performed to induce new transpositions of Ds in new plants derived from cuttings. About 30% of the plants carried at least one Ds that underwent secondary transposition in the later cultures. 8% of transposed Ds elements expressed GUS in various tissues of rice panicles. With cloned DNA adjacent to Ds, the genomic complexities of the insertion sites were examined by Southern hybridization. Half of the Ds insertion sites showed simple hybriodization patterns which could be easily utilized to locate the Ds. Our data demonstrate that the Ac/Ds mediated gene trap system could prove an excellent tool for the analysis of functions of genes in rice. We discuss genetic strategies that could be employed in a largee scale mutagenesis using a heterologous Ac/Ds family in rice.

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Performance Analysis of Hybrid DS/SFH Spread Spectrum System using BFSK Modulations over Nakagami-m Fading Channel with Multitone Jamming (다중톤 재밍이 존재하는 나카가미-­m 페이딩 환경에서 BFSK 변조방식을 이용한 Hybrid DS/SFH 확산대역 시스템의 성능분석)

  • 정근열;박진수
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.8
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    • pp.1629-1637
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    • 2003
  • In this paper, we analyzed the performance of a hybird DS/SFH(Direct­Sequency­Slow Frequency­Hopping) Spread Spectrum system with BFSK modulation over Nakagami­m fading channel with multitone jamming. The performance of the system was improved when a frequency bowing rate increased. In case that process gain of hybrid DS/SFH Spread Spectrum system to be fixed, the hybrid DS/SFH Spread Spectrum takes the low bit error probability than a DS Spread Spectrum system. Also, when the fading index m increases, the fading effect decrease, when the JSR(jamming to signal power ratio) increases ,the performance of a hybrid DS/SFH Spread Spectrum system improved than DS Spread Spectrum system. The result, we have been proved that performance of a hybrid DS/SFH Spread Spectrum was superior to DS Spend Spectrum system over Nakagami­m fading with tome jamming.

Antimicrobial activity by Paenibacillus elgii DS381 and its antimicrobial substances against microbial residents on human skin and pathogenic bacteria (인간 피부 상재균과 병원성 세균에 대한 Paenibacillus elgii DS381과 그 항균물질의 항균활성)

  • Lee, Da-Sol;Song, Hong-Gyu
    • Korean Journal of Microbiology
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    • v.54 no.3
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    • pp.244-253
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    • 2018
  • This study was carried out to evaluate effects of antimicrobial substances produced by isolated soil bacteria. Among two thousands of bacterial isolates Paenibacillus elgii DS381 exhibited high antimicrobial activities against several microbial residents on human skin and pathogenic bacteria. DS381 showed 15.3~26.0 mm inhibition zone diameter against all target bacteria and yeast in agar well diffusion test. Antimicrobial peptide produced by DS381 indicated low minimum inhibitory concentration (0.039-5.000 mg/ml). DS381 produced biosurfactant such as lipopeptide, and surface tension of culture supernatant of DS381 reduced from 60.0 to 40.3 mN/m. DS381 also showed $1.56{\pm}0.13U/ml$ of chitinase activity. These results suggest that Paenibacillus elgii DS381 may be utilized as an efficient biocontrol agent against some important human skin microbes and pathogenic bacteria.

Analysis of CI/DS-CDMA Communication Systems using Interference of Multiple Carriers (다중반송파간섭을 이용한 CI/DS-CDMA 통신시스템 특성분석)

  • 이강봉;이정재
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.05a
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    • pp.129-132
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    • 2001
  • In this paper a new multiple access scheme, CI/DS-CDMA rising the interference of multiple carriers, is introduced. In this system the chip is made up of N orthogonal carriers equally spaced in frequency, where N corresponds to the number of chips in DS-CDMA. The characteristics of CI/DS-CDMA systems in a typical frequency selective fading channel environment, are analyzed. And it is shown that the frequency diversity benefits of this system result in significant performance enhancements relative to traditional DS-CDMA with RAKE receivers.

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A DS-UWB Radar System Based on Correlation Accumulation (상관값 누적 기반 DS-UWB 레이더 시스템)

  • Lee, Youngpo;Yoon, Seokho;Lee, Seong Ro
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38C no.4
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    • pp.359-364
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    • 2013
  • In this paper, we propose a direct sequence ultra wideband (DS-UWB) radar system based on correlation accumulation in the fields of the ship traffic control and the safe ship operation including docking guidance systems. The proposed DS-UWB radar system averages out the noise by accumulating correlator outputs, and thus, provides a reliable distance estimation performance with a shorter estimation time compared with conventional DS-UWB radar systems. From numerical results, it is confirmed that the proposed DS-UWB radar system has not only a shorter average correlation processing time, but also a better distance estimation performance.

The Capacity Analysis of SSB/BPSK-DS/CDMA with Sussessive Interference Canceller (연속 간섭 제거 기법을 적용한 SSB/BPSK-DS/CDMA 방식의 용량 분석)

  • 임명섭
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.11 no.3
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    • pp.484-491
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    • 2000
  • It is necessary to apply SSB modulation method with high bandwidth efficiency to the DS-CDMA mobile communication systems in order to accommodate the increasing number of voice users as well as the broad band and high data rate service in the future. Even though the bandwidth efficiency increases if SSB modulation is applied to BPSK-DS/CDMA, its performance gets degraded because of the increased multiple access interference. Therefore for eliminating the increased multiple access interference, the SSB/BPSK-DS/CDMA with successive interference canceller(SIC) is proposed and its performance and capacity are analyzed. With the limited system bandwidth, it is shown that the SSB/BPSK-DS/CDMA with SIC can accommodate more capacity than the conventional BPSK-DS/CDMA with SIC.

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