• 산업기술연구
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• 제28권A호
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• pp.141-147
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• 2008

Several contaminated bacteria such as Lactobacillus brevis and Pediococcus damnosus in beer production cause beer spoilage by producing off flavours and turbidity. Detection of these organisms is complicated by the strict anaerobic conditions and lengthy incubation times required for their cultivation, consequently there is a need for more rapid detection methods. Recently, two contaminated strains were isolated from vessel of beer production and identified as Lactobacillus species by API kit identificaton as well as 16S-23S ITS sequencing analyses. Two isolated strains were named as Lactobacillus sp. HLA1 and Lactobacillus HLB2, respectively. A polymerase chain reaction (PCR) method was developed for the rapid and specific detection of Lactobacillus sp.. Two sets of primer pairs (HLA1-F/HLA1-R and HLB2-F/HLB2-R) were designed for the amplification of a 1576 base pair (bp) fragment of the HLA1 16S-23S rRNA gene and 1888 bp fragement of the HLB2 16S-23S rRNA. Amplified PCR products were highly specific to detect corresponding bacteria when other contaminated strains were used as PCR templates. However, detection of both strains were limited when $100{\mu}{\ell}$ of cultured samples were mixed with $100m{\ell}$ of beer sample in arbitrary manner. The sensitivity of the assay still needs to be improved for direct detection of the small amounts of bacteria present in beer.

• Journal of Microbiology and Biotechnology
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• 제9권2호
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• pp.184-190
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• 1999

The use of the polymerase chain reaction (PCR) method was described using two sets of primers based on the ceuN gene (JEJ 1 and JEJ 2) which encodes a protein involved in siderophore transport and 16S rRNA gene (pA and pB) for the sensitive and specific detection of enteropathogen Campylobacter jejuni. Six oligonucleotides were utilized in an amplification experiment and PCR products of predicted sizes were generated from whole cells and boiled cell lysates at the same intensity. Two sets of the primer pairs, JEJ and pAB, were specific enough for all C. jejuni strains tested for the direct use of whole cells without DNA extraction or lysis steps. In the PCR using the pAB primer pair, the detection limit, as determined by the ethidium bromide staining of the amplification products on agarose gels, was at the level of $10^1$ bacteria cells or less in both the pure culture and artificially inoculated milk and chicken enrichment samples, whereas the detection limit with the JEJ primer pair was relatively low, i.e. $10^3$ cells or more in the same PCR samples. The PCR method using either a primer JEJ or pAB was both repeatable and specific for the detection of C. jejuni in food. This method is simply completed within 4 h.

• 센서학회지
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• 제32권2호
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• pp.67-74
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• 2023

A microfluidic paper-based analytical device (µPAD) is proposed for the selective detection of ammonia in water by using the modified Berthelot reagent and a fluidic channel consisting of hollow paper. The modified Berthelot reagents were uniformly dispersed in cyclohexane and then immobilized in a detection zone of the µPAD. The loading position of the reagents and the type of a sample flow channel were optimized to achieve a sensitive ammonia detection within a short analytical time. The NH₃ µPAD exhibits a linear colorimetric response to the concentration of ammonia dissolved in water in the range of 1-100 mg L^-1, and its limit-of-detection is 1.75 mg L^-1. In addition, the colorimetric response was not influenced by the addition of 100 mg L^-1 nitrogen containing compounds (sodium nitrate, sodium nitrite, uric acid, hydroxylamine, butylamine, diethylamine) or inorganic salts (NaCl, Na₂HPO₄), presenting the enough selectivity in the detection of water-dissolved ammonia against possible interferents.

• 농촌지도와개발
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• 제7권2호
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• pp.289-293
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• 2000

The way society works in the 21st century differs from that of 20th century, since the people are brought-up to speed regarding current technologies. The www.aflos.pe.kr site and direct e-mailing system were very useful in delivering floricultural information to extension educators, producers, and variety of individuals. The author’s one year experience indicated that extension educators and farmers are receptive to internet technologies, and extension educators have increased the knowledge base of their clientele by responding through direct e-mails. The internet and direct e-mailing systems were popular and powerful way of transferring floricultural information, especially agricultural extension manpower were limited because of localization of extension educators by changing national status to local governments and decreased number of extension educators through government restructuring. The direct e-mailing to approximately 503 individuals resulted about $1{\sim}3%$ responses and the number of phone calls, however virus protection software for e-mail, internet, file servers and desktops to provide the integrated real-time detection of viruses were needed. For more effective operation of direct e-mailing in the future, more specified target groups and specialized organization such as perennials, bulbs, flowering potted plants. and cut flowers. At the same time, things that have worked for last century should not be replaced with new technology, specifically, the value in one-on-one meetings should not be replaced, but rather serve as a supplement.

• Clinical and Experimental Pediatrics
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• 제53권3호
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• pp.397-407
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• 2010

목 적 : F9 유전자는 혈우병B의 병인 유전자이다. 기존의 RFLP를 이용한 연관분석은 정보제공율이 55.6%에 불과하였다. 직접 염기서열 분석법은 98%의 돌연변이를 진단할 수 있지만, 고가의 비용이 든다. 본 연구는 F9 유전자를 대상으로 돌연변이의 선별검사로써 mPCR-CSGE를 사용하고, 이후 특정 유전자 부위만을 염기서열 분석하여 mPCR-CSGE의 유용성을 확인하기 위해 고안되었다. 방 법 : 연구대상은 비혈연 관계인 27명의 혈우병B 환자였다. 직접염기서열 분석법은 독립된 다른 기관에서 시행하였고, mPCR-CSGE 선별 후 염기서열 분석법은 본 연구자의 기관에서 시행되었다. 직접 염기서열 분석법의 결과가 참고치가 되어 mPCR-CSGE 선별 후 염기서열 분석법을 정확성, 경제성, 신속성, 편이성 측면에서 비교하였다. 두가지 방법으로 진단이 되지 않는 환자에게는 MLPA를 이용하여 돌연변이를 발견하였다. 결 과 : 직접 염기서열 분석법으로 26명(96.3%)의 환자에서 돌연변이를 확인할 수 있었다. mPCR-CSGE 선별 후 염기서열 분석법으로는 23명(85.2%)의 환자에서 돌연변이를 찾아낼 수 있었다. 1명의 환자는 MLPA로써 돌연변이를 확인할 수 있었다. 27명의 환자에게 21개의 독립적인 돌연변이가 있었다. mPCR-CSGE 선별 후 염기서열 분석법은 직접 염기서열 분석법에 비해 비용은 55.7%로 줄일 수 있었으나, 실험 단계는 더욱 복잡하였고, 시간도 하루가 더 걸렸으며, 세심한 실험상의 주의가 필요하였다. 결 론 : mPCR-CSGE 선별 후 염기서열 분석법은 85.2%의 높은 돌연변이 선별력을 보이고, 직접 염기서열 분석법의 57.7%의 비용만 소모하였으나, 실험과정에 세한 주의가 요구되었으며, 노동집약적이고, 실험 시간도 하루가 더 소요되었다.

• 한국식품과학회지
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• 제38권2호
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• pp.176-182
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• 2006

본 연구는 축산농가에서 가축의 세균성 질병의 예방과 치료 및 성장촉진을 목적으로 주로 사용되고 있으며, 축산물과 유가공품에 잔류 가능성이 높은 sulfamethazine(SMZ)을 검출할 수 있는 직접경쟁 효소면역분석법(direct competitive ELISA)의 개발과 이를원유 및 시판우유 분석에 이용하는 것을 목적으로 하였다. 면역항원의 합성은 hemiglutarate와 hemisuccinate를 이용하여 SMZ-hemiglutarate(SMZ-HG)와 SMZ-hemisuccinate(SMZ-HS) hapten을 유도한 후 단백질 KLH와 STI를 결합시켜 마우스 면역에 사용하였고, SMZ-HG-KLH를 이용하여 면역한 마우스에서 가장 높은항체 생성정도를 나타내었다. 세포융합과 cloning을 실시하여 총15종의 hybridoma cell line을 확보하였고 그 중 가장 경쟁성이 뛰어나고 민감도가 높은 1H11-5 hybridoma를 선택하고 대량 생산하였다. 생산된 항체는 sulfamethazine에만 54%의 교차 반응성을 나타내었고, 다른 설파계 항생제와는 반응을 하지 않는 특이성이 높은 항체로 확인되었고 이를 이용하여 확립된 direct competitive ELISA법은 검출범위가 0.1-100 ppb 수준으로 기존에 보고된 ELISA보다 민감도가 높았다. 민감도와 특이성이 높은 direct competitive ELISA를 이용하여 원유와 시판우유를 분석하기 위한 전처리법을 확립하여 회수율을 확인한 결과 원유의 경우 82-121%까지 회수가 되는 것으로 나타났으며, 시판유의 경우는 82-97%까지 회수가 되는 것으로 나타나 우유 샘플 중에 미량 잔류하는 SMZ를 신속하고 정확하게 분석할 수 있을 것으로 사료되었다. 이러한 연구결과를 종합해 볼 때 확립된 direct competitive ELISA법은 우유 시료뿐만 아니라 모든 축산물에 잔류 가능성이 높은 SMZ의 분석을 신속하고 정확하게 분석이 가능할 것으로 사료되었고 확립된 direct competitive ELISA법의 안정화 조건을 확립하고 응용한다면 외국으로부터 생산 및 수입되는 ELISA kit을 대체할 수 있는 저가형 국산화 ELISA kit의 상용화가 가능할것으로 사료되었다.

• 대한전기학회논문지
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• 제40권1호
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• pp.31-38
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• 1991

A direct digital control technique of a current source using the phase-controlled rectifier is presented. A digital firing technique without sensing the line voltage is proposed. This scheme generates firing pulses directly from error signal between command and output voltage. Thus the phase detection transformers filters and zero-crossing detector are unnecessary. The synchronism is modeled and analized. Also a software synchronization algorithm is presented without a look up table and controls the system in real time with fast dynamic characteristics. Using the single-chip microprocessor 8097BH, the direct digital control is implemented with minimal hardware structure. Using the time-weighted performance index, the optimal discrete IPM control technique is also proposed to control the current of the PCR.

• 환경위생공학
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• 제10권3호
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• pp.35-44
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• 1995

This study was carried out in order to compare the methods for Salmonella spp. isolation from sewage and to settle the most appropriate conditions for that isolation. The direct enrichment method was more effective than the pre- enrichment method for Salmonella spp. isolation. The rate of detection was much higher when the specimens were enriched at $41.5^{\circ}C$ than when at $35^{\circ}C$. Usage of XLBG agar medium showed better results for Salmonella isolation than that of SS medium. It can be suggested that the most effective combination for Salmonella spp. isolation was the direct centrifugation(3,000 rpm 100m1)- direct enrichment($41.5^{\circ}$C)-usage of XLBG medium.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2012년도 한국컴퓨터종합학술대회논문집 Vol.39 No.1(D)
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• pp.135-136
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• 2012

윈도우기반 게임 프로그램의 엔진은 대부분 DirectX를 사용하고 있다. 이는 게임 프로세스를 탐지하는데에 있어서 수많은 게임의 이름을 알고 있지 않아도, DirectX의 사용여부로 게임 프로세스를 탐지할 수 있음을 의미한다. 본 논문은 유저모드 후킹 Windows Message Hooking과 Direct3D Hooking을 이용하여 게임 프로세스를 탐지하는 방법을 제안하고자 한다.

• 한국음향학회지
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• 제2권1호
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• pp.11-19
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• 1983

An irregulary formed chamber was designed and constructed to recognize the direct sound radiated from the sound source and the reflected sound from the walls of the chamber. The sound signal used was tone burst in the frequency response characteristics with the signal detection after transient effect. The direct wave, transient phenomena and the primary reflected sound could be asiily distinguished each other by measurements of the arrival time of the time difference. And also noise could be easily distinguished by the same method. The result obtained can be used in industries for automatic measurement of the sound pressure reponse characteristics with respect to frequencies.