• ETRI Journal
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• 제41권4호
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• pp.426-436
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• 2019

In time division duplex (TDD)-based multiuser massive multiple input multiple output (MIMO) systems, the uplink channel is estimated and the results are used in downlink for signal detection. Owing to noisy uplink channel estimation, the downlink channel should also be estimated for accurate signal detection. Therefore, recently, a blind method was developed, which assumes the use of a linear high-power amplifier (HPA) in the base station (BS). In this study, we extend this method to a scenario with a nonlinear HPA in the BS, where the Bussgang decomposition is used for HPA modeling. In the proposed method, the average power of the received signal for each user is a function of channel gain, large-scale fading, and nonlinear distortion variance. Therefore, the channel gain is estimated, which is required for signal detection. The performance of the proposed method is analyzed theoretically. The simulation results show superior performance of the proposed method compared to that of the other methods in the literature.

• Journal of Communications and Networks
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• 제18권1호
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• pp.27-39
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• 2016

This paper derives and analyzes a novel block fast Fourier transform (FFT) based joint detection algorithm. The paper compares the performance and complexity of the novel block-FFT based joint detector to that of the Cholesky based joint detector and single user detection algorithms. The novel algorithm can operate at chip rate sampling, as well as higher sampling rates. For the performance/complexity analysis, the time division duplex (TDD) mode of a wideband code division multiplex access (WCDMA) is considered. The results indicate that the performance of the fast FFT based joint detector is comparable to that of the Cholesky based joint detector, and much superior to that of single user detection algorithms. On the other hand, the complexity of the fast FFT based joint detector is significantly lower than that of the Cholesky based joint detector and less than that of the single user detection algorithms. For the Cholesky based joint detector, the approximate Cholesky decomposition is applied. Moreover, the novel method can also be applied to any generic multiple-input-multiple-output (MIMO) system.

• 한국축산식품학회지
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• 제40권4호
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• pp.628-635
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• 2020

The objective of this study was to detect three non-halal meat products consisted of dog, pork, and rat species in meatball using novel multiplex-PCR with 12S rRNA gene as target sites. A total of 33 self-made meatballs were used, and they were grouped into eleven types of meatball based on meat species origin contained in the meatballs. Each type consisted of three meatballs. Extraction of genomic DNA from the meatballs was used as a DNA template for simplex-, duplex-, and multiplex-PCR processes. The result of simplex-PCR, duplex-PCR, and multiplex-PCR showed that the 12S rRNA primer gene successfully amplified DNA for each species bovine, dog, pig, and rat, which are respectively indicated by 155, 244, 357, and 491 bp of DNA bands. In addition, multiplex-PCR with 12S rRNA gene primers can be uniquely and accurately used for detection bovine, dog, pig, and rat species on beef meatball in one reaction.

• 한국가금학회지
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• 제44권2호
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• pp.93-102
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• 2017

본 연구에서 NDV의 L유전자와 F유전자를 표적 부위로 각각 제작한 primer 세트를 사용함으로써 하나의 PCR 튜브에서 NDV 검출(386 bp의 증폭 크기)과 함께 병원성 NDV(229 bp의 증폭 크기)를 동시에 감별 증폭할 수 있는 dRT-PCR 검사법을 개발하였다. 개발된 dRT-PCR검사법은 NDV를 특이적으로 검출하고, 병원성을 감별하였다. 특히 국내 병성감정 실시기관에서 적용 중인 기존의 RT-PCR 상용키트에서는 검출하지 못하는 class I NDV과 PPMV(class II 유전형 VI형)을 NDV를 검출함과 동시에 병원성 NDV도 감별가능하였다. 개발된 dRT-PCR 검사법의 검출 민감도는 약 $10^{3.0}EID_{50}/0.1mL$로 평가되었다. 또한 ND발생국의 야외 시료에 적용했을 때, NDV 공통항원 검출율은 94.4%였으며, 병원성 NDV 검출율은 100%이었다. 그러므로 본 연구에서 개발한 dRT-PCR 검사법은 의심축 사례에서 ND를 신속 정확하게 진단하는 데 유용할 진단 방법을 제공할 수 있을 것으로 판단된다.

• The Plant Pathology Journal
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• 제34권6호
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• pp.490-498
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• 2018

Panicle blight and seed rot disease caused mainly by Burkholderia glumae and Burkholderia gladioli is threatening rice cultivation worldwide. The bacteria have been reported as seed-borne pathogens from rice. Accurate detection of both pathogens on the seeds is very important for limiting the disease dissemination. Novel primer pairs targeting specific molecular markers were developed for the robust detection of B. glumae and B. gladioli. The designed primers were specific in detecting the target species with no apparent cross-reactions with other related Burkholderia species at the expected product size. Both primer pairs displayed a high degree of sensitivity for detection of B. glumae and B. gladioli separately in monoplex PCR or simultaneously in duplex PCR from both extracted gDNA and directly preheated bacterial cell suspensions. Limit of detection was as low as 0.1 ng of gDNA of both species and $3.86{\times}10^2cells$ for B. glumae and $5.85{\times}10^2cells$ for B. gladioli. On inoculated rice seeds, the designed primers could separately or simultaneously detect B. glumae and B. gladioli with a detection limit as low as $1.86{\times}10^3cells$ per rice seed for B. glumae and $1.04{\times}10^4cells$ per rice seed of B. gladioli. The novel primers maybe valuable as a more sensitive, specific, and robust tool for the efficient simultaneous detection of B. glumae and B. gladioli on rice seeds, which is important in combating rice panicle blight and seed rot by early detection and confirmation of the dissemination of pathogen-free rice seeds.

• 식물병연구
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• 제15권2호
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• pp.57-62
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• 2009

우리나라 벼에 발생하는 주요 바이러스 중 애멸구에 의하여 전염하는 벼줄무의잎마름병(RSV)과 벼검은줄오갈병(RBSDV)에 대한 간편한 유전자 진단법인 VCHT-PCR 방법을 개발하였다. 벼 잎의 경우 즙액 추출 완충액은 0.5% sodium sulfite를 첨가한 0.01 M 인산완충액(pH 7.0)을 기본 완충액으로 이용하고 애멸구를 진단할 경우에는 기본 완충액에 2% PVP을 첨가하였을 때 VC/RT-PCR 진단이 잘 되었다. VC/RT-PCR을 이용한 진단에 적합한 RSV와 RBSDV 프라이머를 선발하였고 이것을 이용하여 동시진단으로 경기도 김포, 평택, 시흥지역에서 채집한 애멸구의 RSV와 RBSDV의 보독충을 쉽고 경제적으로 진단 할 수 있었다. ELISA에 의한 진단결과와 비교할 때 세 지역을 합하여 RSV에 대한 평균 보독충률은 9.2%로 동일하였으나 보독충 중 일부가 ELISA와 VC/RT-PCR 두 방법에 의한 진단결과가 다르게 나온 것은 RSV의 혈청학적, 유전적 계통 존재 가능성을 제시하고 있다. 포장에서 채집한 애멸구의 VC/RT-PCR 진단효율은 RSV와 RBSDV를 동시에 진단하므로 써 RSV만 진단이 가능한 ELISA 결과 보다 3.2% 높았다.

• 대한임상검사과학회지
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• 제45권1호
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• pp.16-20
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• 2013

Outbreaks of vancomycin-resistant enterococci (VRE) are being reported more frequently in many countries. While seven glycopeptide resistance genotypes have been described in Enterococci, vanA and vanB are the most common resistance genotypes. The aim of this study was to detect antibiotic susceptibilities of 23 Enterococcus faecium strains, which caused an outbreak in a University hospital by a disk diffusion test to investigate the presence of the species specific gene, and the resistant genotypes, vanA and vanB by duplex PCR. PCR for vanA and vanB was performed on 23 enterococci. Twenty three were identified as E. faecium and were tested positive for the vanA genotype. This study will report on the validation of a simple and accurate VRE detection method that can be easily incorporated into the daily routine of a clinical laboratory. Early detection of VRE strains, including those with susceptibility to vancomycin, is of paramount clinical importance as it allows rapid initiation of strict infection control practices, as well as the therapeutic guidance for confirmed infections. The PCR method developed in the present study is simple and reliable for the rapid characterization of VRE.

• 농업과학연구
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• 제49권4호
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• pp.795-807
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• 2022

The development and commercialization of industrial genetically modified (GM) organisms is actively progressing worldwide, highlighting an increased need for improved safety management protocols. We sought to establish an environmental monitoring method, using real-time polymerase chain reaction (PCR) and propidium monoazide (PMA) treatment to develop a quantitative detection protocol for living GM microorganisms. We developed a duplex TaqMan quantitative PCR (qPCR) assay to simultaneously detect the selectable antibiotic gene, ampicillin (AmpR), and the single-copy Escherichia coli taxon-specific gene, D-1-deoxyxylulose 5-phosphate synthase (dxs), using a direct cell suspension culture. We identified viable engineered E. coli cells by performing qPCR on PMA-treated cells. The theoretical cell density (true copy numbers) calculated from mean quantification cycle (Cq) values of PMA-qPCR showed a bias of 7.71% from the colony-forming unit (CFU), which was within ±25% of the acceptance criteria of the European Network of GMO Laboratories (ENGL). PMA-qPCR to detect AmpR and dxs was highly sensitive and was able to detect target genes from a 10,000-fold (10^-4) diluted cell suspension, with a limit of detection at 95% confidence (LOD_95%) of 134 viable E. coli cells. Compared to DNA-based qPCR methods, the cell suspension direct PMA-qPCR analysis provides reliable results and is a quick and accurate method to monitor living GM E. coli cells that can potentially be released into the environment.

• International Journal of Oral Biology
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• 제44권1호
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• pp.8-13
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• 2019

Recently, the importance of on-site detection of pathogens has drawn attention in the field of molecular diagnostics. Unlike in a laboratory environment, on-site detection of pathogens is performed under limited resources. In this study, we tried to optimize the experimental conditions for on-site detection of pathogens using a combination of ultra-fast convection polymerase chain reaction (cPCR), which does not require regular electricity, and nucleic acid lateral flow (NALF) immunoassay. Salmonella species was used as the model pathogen. DNA was amplified within 21 minutes (equivalent to 30 cycles of polymerase chain reaction) using ultra-fast cPCR, and the amplified DNA was detected within approximately 5 minutes using NALF immunoassay with nucleic acid detection (NAD) cassettes. In order to avoid false-positive results with NAD cassettes, we reduced the primer concentration or ultra-fast cPCR run time. For singleplex ultra-fast cPCR, the primer concentration needed to be lowered to $3{\mu}M$ or the run time needed to be reduced to 14 minutes. For duplex ultra-fast cPCR, $2{\mu}M$ of each primer set needed to be used or the run time needed to be reduced to 14 minutes. Under the conditions optimized in this study, the combination of ultra-fast cPCR and NALF immunoassay can be applied to on-site detection of pathogens. The combination can be easily applied to the detection of oral pathogens.

• 한국통신학회논문지
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• 제38C권3호
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• pp.239-246
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• 2013

기존 IEEE 802.15.4는 PHY 계층과 MAC 계층에서의 표준을 제공하며 저전력, 저대역폭, 저속 데이터 통신을 특징으로 한다. 이러한 한계점으로 인하여 IEEE 802.15.4는 센서 검출, 홈 네트워크 등의 제한된 용도로만 쓰였으나 최근 음성과 같은 멀티미디어 데이터를 전송하려는 연구가 활발히 진행되고 있다. 본 논문에서는 기존 센서 네트워크 기반 Peer-to-Peer 음성 통신의 개선을 통해 다수 사용자간의 음성 통신을 지원하기 위하여 새로운 IEEE 802.15.4 PHY 기반 TDMA/TDD MAC을 설계하고 그룹 통신을 할 수 있는 하드웨어를 개발 하였다. 또한 설계된 시스템의 성능을 평가하기 위하여 실험을 통해 Mean Opinion Score (MOS)를 측정 하였으며 이는 사인파를 사용하는 방법을 이용하여 검증하였고 본 논문에서 제안하는 시스템이 실제 환경에서 다양한 응용 솔루션으로 개발 될 수 있음을 기대하였다.