• 전기전자학회논문지
• /
• 제10권1호
• /
• pp.22-29
• /
• 2006

본 논문에서는 마이크로프로세서와 주변블록 사이에서 SDRAM을 사용함에 있어서 DMA(Direct Memory Access)에 의한 효율적인 SDRAM 접근방식을 제시하고 있다. 여기에서 마이크로프로세서는 AMBA 버스를 통해서 SDRAM에 접근을 하고 DMA는 DMA 전용 버스를 통해서 SDRAM에 접근한다. 마이크로프로세서가 SDRAM에 접근하지 않고 다른 레지스터에 접근하거나, 아니면 마이크로프로세서 캐쉬에서 히트(hit)신호가 발생하여 SDRAM에 접근할 필요가 없을 때에 주변 블록에서는 DMA를 통해서 SDRAM에 접근하여 데이타를 읽거나 쓰기 동작을 통해서 SDRAM을 효율적으로 사용할 수 있다. 이 방법은 DMA가 마이크로프로세서의 SDRAM 억세스를 최소한의 방해로 SDRAM을 사용할 수 있다. 이와 같은 방법을 이용함으로써 전체적인 시스템 효율을 높여 약 16.8% 정도의 성능 향상 효과를 가져옴을 확인 할 수 있었다.

• 한국콘텐츠학회논문지
• /
• 제9권9호
• /
• pp.9-17
• /
• 2009

RFID(Radion Frequency Identification)는 바코드를 대체할 차세대 기술이다. RFID는 무선 주파수를 사용하여 RFID 태그 내부에 있는 ID를 읽어 물체를 식별할 수 있다. 하지만 RFID 태그는 어떤 리더의 요청에도 자신의 고유 ID를 무선 통신으로 응답하기 때문에 도청이나 불법 리더로부터 보안이나 프라이버시에 대한 공격에 취약하다. RFID 인증 프로토콜은 보안과 프라이버시 문제를 해결하기 위해 활발히 연구되고 있으며 태그 검색에도 사용되고 있다. 최근에는 RFID 시스템에서 태그의 수가 증가하고 데이터 수집 비용도 늘어나면서 효과적인 태그 검색에 대한 비중이 더 많아졌다. 본 논문에서는 보안과 프라이버시 보호를 위한 필요조건을 보장하는 Miyako Ohkubo의 hash-chain 메커니즘에서 데이터베이스 연산량이 많은 문제점을 Tag-Grouping을 통해 보완한 효율적인 검색 방법을 제안한다. 실험 결과 데이터베이스에서 10만개의 레코드 수를 기준으로 접근비율이 5이상인 태그 그룹의 우선 검색시 약 30%의 검색시간이 감소 하였다.

• 한국건축시공학회지
• /
• 제11권3호
• /
• pp.238-246
• /
• 2011

Choosing the best-performance materials is a crucial task for the successful completion of a project in the construction field. In general, the process of material selection is performed through the use of information by a highly experienced expert and the purchasing agent, without the assistance of logical decision-making techniques. For this reason, the construction field has considered various artificial intelligence (AI) techniques to support decision systems as their own selection method. This study proposes the application of a systematic and efficient support vector machine (SVM) model to select optimal exterior materials. The dataset of the study is 120 completed construction projects in South Korea. A total of 8 input determinants were identified and verified from the literature review and interviews with experts. Using data classification and normalization, these 120 sets were divided into 3 groups, and then 5 binary classification models were constructed in a one-against-all (OAA) multi classification method. The SVM model, based on the kernel radical basis function, yielded a prediction accuracy rate of 87.5%. This study indicates that the SVM model appears to be feasible as a decision support system for selecting an optimal construction method.

• Journal of Life Science
• /
• 제11권1호
• /
• pp.52-56
• /
• 2001

The present study intends to characterize the DNA damage-inducible responses in eukaryotic cells. The fission yeast, S. pombe, which displays efficient DNA repair systems, was used in this study as a model system for higher eukaryotes. To study UV-inducible responses in S. pombe, five UV-inducible cDNA clones were isolated from S. pombe by using subtration hybridization method. To investigate the expression of isolated genes, the cellular levels of the transcripts of these genes were determined by Northern blot analysis after UV-irradiation. The transcripts of isolated gene (UV130) increased rapidly and reached maximum accumulation after UV-irradiation. Compared to the message levels of control, the levels of maximal increase were approximately 5 fold to UV-irradiation. In order to investigation whether the increase of UV130 transcripts was a specific results of UV-irradiation, UV130 transcript levels were examined after treating the cells to Methylmethane sulfonate (MMS). The transcripts of UV130 were not induced by treatment of 0.25% MMS. These results implied that the effects of damaging agents are complex and different regulatory pathways exist for the induction of these genes. To characterize the structure of UV130 gene, nucleotide sequences were analyzed. The nucleotide sequence of 1,340 nucleotide excluding poly(A) tail contains one open reading frame, which encodes a protein of 270 amino acids. The predicted amino acid sequences of UV130 do not exhibit any significant similarity to ther known sequences in the database.

• 동의신경정신과학회지
• /
• 제16권2호
• /
• pp.243-249
• /
• 2005

주의력결핍 과잉행동장애로 진단한 7세 남아에게 주 2회 3개월간의 뉴로피드백 치료를 통하여 일상생활의 산만한 행동의 개선과 단축형 Conner 평가척도, 한국아동인성검사 BASA읽기검사 등에서 개선된 결과 및 주의집중 뇌파 지표가 향상되는 경과를 관찰할 수 있었다. 이후 확대된 임상적용과 연구가 필요하리라 사료된다.

• 한국작물학회지
• /
• 제50권4호
• /
• pp.286-290
• /
• 2005

Ascorbate peroxidase (APX) plays a crucial role in the detoxification of hydrogen peroxide. APX activity is maintained significantly higher in the paraquat­treated leaves of the paraquat-tolerant Rehmannia glutinos. This study was conducted to understand structural and regulatory characteristics of APX gene in R. glutinosa. A putative APX cDNA clone (RgAPX1) was isolated from a leaf cDNA library using a partially sequenced expressed sequence tag clone. RgAPX1 is consisted of 1148 bp nucleotides and contains an open reading frame encoding a 250 amino acid-long polypeptide. Deduced RgAPX1 amino acid sequence shares higher sequence similarity to cytosolic APXs. RgAPX1. expression was higher in the leaf than in the flower and root. Southern blot result indicates the presence of one or two RgAPX1-related genes in R. glutinosa genome. RgAPX1 transcription was affected differentially by various stresses and phytohormone. The results indicate that RgAPXl is constitutively expressed in most tissues and its expression is modulated for the immediate and efficient detoxification of $H_2O_2$ under normal and stress conditions.

• 한국농공학회지
• /
• 제32권3호
• /
• pp.102-115
• /
• 1990

Importance of anaerobic digestion as an energy generating device has been increased as fuel shortage becomes serieous. Several modification methods on the conventional digesters including Powdered Activated Carbon (PAC) addition and two-phase digestion were studied to enhance the gas production. This study investigated the effects of PAC on anaerobic digestion of chicken manure in terms of gas production and sludge stabilization. As a first experiment, an optimum PAC dose for efficient gas production was determined in a batch test. In semi-continuous experiments, an optimum Sludge Retention Time (SRT) at that PAC concentration and an overall substate utilization rate coefficient were investigated. A portion of gas increased by PAC addition was estimated using a substrate utilization rate coefficient of microorganisms attached on PAC. This test was performed in batch experiments using acetic acid as a substrate. The digesters for all experiments were kept 35${\pm}$ 1˚C in a heated water bath. Mixing was performed manually once a day and the produced gas was collected for daily reading. The following conclusions were made for this study. 1. Cptimum PAC concentration was 5% total solids, where gas production rate was increased by 20 percents. 2. Optimum SRT was 7.5 days. 3. Substrate utilization rate coefficient of microorganisms attached on PAC was about twice as much as that of suspended ones.

• Journal of Microbiology and Biotechnology
• /
• 제25권6호
• /
• pp.887-892
• /
• 2015

Uricase is an important microbial enzyme that can be used in the clinical treatment of gout, hyperuricemia, and tumor lysis syndrome. A total of 127 clinical isolates of Pseudomonas aeruginosa were tested for uricase production. A Pseudomonas strain named Ps43 showed the highest level of native uricase enzyme expression. The open reading frame of the uricase enzyme was amplified from Ps43 and cloned into the expression vector pRSET-B. Uricase was expressed using E. coli BL21 (DE3). The ORF was sequenced and assigned GenBank Accession No. KJ718888. The nucleotide sequence analysis was identical to the coding sequence of uricase gene puuDof P. aeruginosa PAO1. We report the successful expression of P. aeruginosa uricase in Escherichia coli. E. coli showed an induced protein with a molecular mass of about 58 kDa that was confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting. We also established efficient protein purification using the Ni-Sepharose column with activity of the purified enzyme of 2.16 IU and a 2-fold increase in the specific activity of the pure enzyme compared with the crude enzyme.

• 전자공학회논문지SC
• /
• 제40권4호
• /
• pp.282-290
• /
• 2003

전력선 통신을 이용한 기존의 원격검침 시스템은 설치가 복잡하고 비용이 많이 든다. 현대 국내의 대부분의 아파트 및 다세대주택에 인터넷사업자에 의하여 이미 상용화된 인터넷망이 구축되어 있음에 따라 전력회사의 독자적인 네트워크장비가 아닌 인터넷 사업자에 의하여 펼쳐진 인터넷망을 이용하여 저속 전력선통신 모뎀과 웹서버와의 연결로서 저가이고 구조가 간단하여 시스템의 구성이 간편한 원격검침 및 원격제어 시스템 구성을 목적으로 총 2가지의 하드웨어와 2가지의 소프트웨어를 설계 및 제작하였다.

• 한국인터넷방송통신학회논문지
• /
• 제10권2호
• /
• pp.53-59
• /
• 2010

안드로이드는 구글(Google)과 오픈 핸드셋 얼라이언스(Open Handset Alliance)가 만들어낸 모바일폰용 오픈소스 소프트웨어 툴킷(toolkit)이다. 안드로이드는 몇 년 내로 수백만 개의 핸드폰 및 그 밖의 모바일 장치에 사용될 것이며, 응용프로그램 개발자들의 주요 플랫폼이 될 것이다. 본 논문에서는 구글의 안드로이드 플랫폼을 기반으로 하여 웹뷰(Webview)의 장점과 구글의 검색기능을 활용하여 새로운 애플리케이션 컨텐츠 Booky를 개발한다. 개발된 Booky 컨텐츠의 특징은 다음과 같다. 첫째, 모바일 기반의 웹 브라우저로서 일반적인 웹브라우저보다 향상된 화면 해상도 기능과 데이터 전송량을 줄여서 보다 빠른 화면(View) 기능을 가지고 있다. 둘째, 효과적인 E-book 검색(Search) 및 리딩 기능을 가지고 있다. 성능평가는 AVD(Android Virture Device)를 사용하여 시뮬레이션하였다.