• 제목/요약/키워드: signal alignment

검색결과 138건 처리시간 0.026초

무릎 자기공명영상에서 지역적 확률 아틀라스 정렬 및 반복적 그래프 컷을 이용한 전방십자인대 분할 (Anterior Cruciate Ligament Segmentation in Knee MRI with Locally-aligned Probabilistic Atlas and Iterative Graph Cuts)

  • 이한상;홍헬렌
    • 정보과학회 논문지
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    • 제42권10호
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    • pp.1222-1230
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    • 2015
  • 무릎 자기공명영상에서 전방십자인대의 분할은 밝기값의 불균일성 및 주변 조직들과의 유사 밝기값 특성으로 인해 기존 분할기법의 적용에 한계가 있다. 본 논문에서는 지역적 정렬을 통한 확률아틀라스 생성 및 반복적 그래프 컷을 통한 다중아틀라스 기반 전방십자인대 분할기법을 제안한다. 첫째, 전역 및 지역적 다중아틀라스 강체정합을 통해 전방십자인대의 확률아틀라스를 생성한다. 둘째, 생성된 확률아틀라스를 이용하여 최대사후추정 및 그래프 컷을 통하여 전방십자인대 초기 분할을 수행한다. 셋째, 마스크 기반 강체정합을 통한 형상정보 개선 및 반복적 그래프 컷을 통해 전방십자인대 분할 개선을 수행한다. 제안방법의 성능평가를 위하여 육안평가 및 정확성평가를 수행하였으며, 평가 결과 제안방법의 Dice 유사도는 75.0%, 평균표면거리는 1.7화소, 제곱근표면거리는 2.7화소로서 기존 그래프 컷 방법에 비하여 전방 십자인대의 분할정확도가 각각 12.8%, 22.7%, 및 22.9% 향상된 것으로 나타났다.

Cloning, Expression, and Characterization of Bacillus sp. snu-7 Inulin Fructotransferase

  • Kim, Chung-Sei;Hong, Chang-Ki;Kim, Kyoung-Yun;Wang, Xiu-Ling;Kang, Su-Il;Kim, Su-Il
    • Journal of Microbiology and Biotechnology
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    • 제17권1호
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    • pp.37-43
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    • 2007
  • A gene encoding inulin fructotransferase (di-D-fructofuranose 1,2': 2,3' dianhydride [DFA III]-producing IFTase, EC 4.2.2.18) from Bacillus sp. snu-7 was cloned. This gene was composed of a single, 1,353-bp open reading frame encoding a protein composed of a 40-amino acid signal peptide and a 410-amino acid mature protein. The deduced amino acid sequence was 98% identical to Arthrobacter globiformis C11-1 IFTase (DFA III-producing). The enzyme was successfully expressed in E. coli as a functionally active, His-tagged protein, and it was purified in a single step using immobilized metal affinity chromatography. The purified enzyme showed much higher specific activity (1,276 units/mg protein) than other DFA III-producing IFTases. The recombinant and native enzymes were optimally active in very similar pH and temperature conditions. With a 103-min half-life at $60^{\circ}C$, the recombinant enzyme was as stable as the native enzyme. Acidic residues and cysteines potentially involved in the catalytic mechanism are proposed based on an alignment with other IFTases and a DFA IIIase.

Novel Peptide Nucleic Acid Melting Array for the Detection and Genotyping of Toxoplasma gondii

  • Suh, Soo Hwan;Yun, Han Seong;Lee, Sang-Eun;Kwak, Hyo-Sun
    • 한국미생물·생명공학회지
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    • 제47권4호
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    • pp.645-650
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    • 2019
  • Despite differences in virulence between strains of Toxoplasma gondii, rapid and accurate genotyping methods are lacking. In this study, a method was developed to detect and genotype T. gondii in food and environmental samples using PCR and a novel peptide nucleic acid (PNA) melting array. An alignment of genome sequences for T. gondii type I, II, and III obtained from NCBI was generated, and a single nucleotide polymorphism analysis was performed to identify targets for PCR amplification and a PNA melting array. Prior to the PNA melting array, conventional PCR was used to amplify GRA6 of T. gondii. After amplification, the PNA melting array was performed using two different PNA hybridization probes with fluorescent labels (FAM and HEX) and quenchers. Melting curves for each probe were used to determine genotypes and identify mutations. A 214-bp region of the GRA6 gene of T. gondii was successfully amplified by PCR. For all T. gondii strains (type I, II, and III) used to evaluate specificity, the correct genotypes were determined by the PNA melting array. Non-T. gondii strains, including 14 foodborne pathogens and 3 protozoan parasites, such as Giardia lamblia, Cryptosporidium parvum, and Entamoeba histolytica, showed no signal, suggesting that the assay has a high specificity. Although this is only a proof-of-concept study, the assay is promising for the fast and reliable genotyping of T. gondii from food and environmental samples.

Identification and Expression Patterns of fvexpl1, an Expansin-Like Protein-Encoding Gene, Suggest an Auxiliary Role in the Stipe Morphogenesis of Flammulina velutipes

  • Huang, Qianhui;Han, Xing;Mukhtar, Irum;Gao, Lingling;Huang, Rongmei;Fu, Liping;Yan, Junjie;Tao, Yongxin;Chen, Bingzhi;Xie, Baogui
    • Journal of Microbiology and Biotechnology
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    • 제28권4호
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    • pp.622-629
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    • 2018
  • Expansins are cell wall proteins that mediate cell wall loosening and promote specific tissue and organ morphogenesis in plants and in some microorganisms. Unlike plant expansins, the biological functions of fungal expansin-like proteins have rarely been discussed. In the present study, an expansin-like protein-encoding fvexpl1 gene, was identified from Flammulina velutipes by using local BLAST. It consisted of five exons with a total length of 822 bp. The deduced protein FVEXPL1 contained 274 amino acids with a predicted molecular mass and isoelectric point of 28,589 Da and pH 4.93, respectively. The first 19 amino acids from the N terminal are the signal peptide. Phylogenetic analysis and multiple protein alignment indicated FVEXPL1 was an expansin-like protein. The expression level of fvexpl1 gene in the stipe was significantly higher than that in the mycelia, primordia, and cap. However, the expression level of fvexpl1 gene was significantly higher in the fast elongation region of the stipe as compared with the slow elongation region. Expression analysis indicated that fvexpl1 gene might have an auxiliary role in the stipe morphogenesis of F. velutipes.

cDNA Sequence and mRNA Expression of a Putative Alcohol Dehydrogenase from the Mole Cricket, Gryllotalpa orientalis

  • Kim, Iksoo;Lee, Kwang-Sik;Jin, Byung-Rae;Lee, Young-Sin;Ryu, Kang-Sun
    • International Journal of Industrial Entomology and Biomaterials
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    • 제7권1호
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    • pp.37-44
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    • 2003
  • Alcohol dehydrogenases (AHDs) are enzymes responsible for the catalysis of the reversible conversion of various alcohols to their corresponding aldehydes and ketonesis. Until now cDNA sequences of ADH gene is informed exclusively from several diptean species. We describe here the cDNA sequence and mRNA expression of a putative ADH gene from the mole cricket, Gryllotalpa orientalis, and phylogenetic relationships among known insect ADHs. The G. orientalis ADH cDNA sequences comprised of 798 bp encoding 266 amino acid residues. The multiple sequence alignment of G. orientalis ADH gene and known dipteran ADHs shared 100% identity in the nine amino acid residues that are important for the enzymatic activity in Drosophila melanogaster. Percent sequence identity ranged from 25% to 32% among all insect ADHs including both types of ADHs. G. orientalis ADH gene showed no clear resemblance to any dipteran species and type. Phylogenetic analysis of the deduced amino acid sequences of G. orientalis ADH gene with available dipteran ADH genes including both types of ADHs further confirmed that the G. orientalis ADH gene is not clearly assigned to either type of ADHs. Northern blot analysis revealed a stronger signal in the fat body than midgut and epidermis, indicating that the fat body possibly is a main site for the synthesis of the G. orientalis ADH protein.

가속도계 신호 처리 오차의 관성항법장치 영향 분석 (Effects of Accelerometer Signal Processing Errors on Inertial Navigation Systems)

  • 성창기;이태규;이정신;박재용
    • 한국군사과학기술학회지
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    • 제9권4호
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    • pp.71-80
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    • 2006
  • Strapdown Inertial navigation systems consist of an inertial sensor assembly(ISA), electronic modules to process sensor data, and a navigation computer to calculate attitude, velocity and position. In the ISA, most gryoscopes such as RLGs and FOGs, have digital output, but typical accelerometers use current as an analog output. For a high precision inertial navigation system, sufficient stability and resolution of the accelerometer board converting the analog accelerometer output into digital data needs to be guaranteed. To achieve this precision, the asymmetric error and A/D reset scale error of the accelerometer board must be properly compensated. If the relation between the acceleration error and the errors of boards are exactly known, the compensation and estimation techniques for the errors may be well developed. However, the A/D Reset scale error consists of a pulse-train type term with a period inversely proportional to an input acceleration additional to a proportional term, which makes it difficult to estimate. In this paper, the effects on the acceleration output for auto-pilot situations and the effects of A/D reset scale errors during horizontal alignment are qualitatively analyzed. The result can be applied to the development of the real-time compensation technique for A/D reset scale error and the derivation of the design parameters for accelerometer board.

발작성 심방세동 환자의 P파 간격 측정 방법에 관한 연구 (A Study for measurement method of P-wave duration in Paroxysmal Atrial Fibrillation(PAF) subjects)

  • 이종연;여형석;한완택;김인영;이병채;김준수;민정선;서정돈;이원로
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1998년도 추계학술대회
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    • pp.181-182
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    • 1998
  • In previous study for correlation between P-wave Signal Averaged Electrocardiography (SAECG) and Paroxysmal Atrial Fibrillation (PAF) subjects, we showed that the duration of P-wave in subjects is longer than in controls. In this respect, the P-wave SAECG is a new method proving to be an accurate and independent noninvasive marker for the risk of PAF. To prove this suggestion, accurate detection and alignment of P-wave are indispensible. In previous study, we measured P-wave duration by manual. So it was not accurate and consistent. To measure the P-wave duration accurately and automatically, we have developed an automatic algorithm for P-wave duration measurement. We showed that the duration of P- wave in the subjects is longer than in controls with this algorithm.

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나노튜브/화학연료의 동축 구조에서 생성되는 열동력 파도를 이용한 전기 에너지 생성 (Thermopower Wave in Core-Shell Structures of Carbon Nanotube Chemical Fuels)

  • 최원준;마이클 스트라노
    • 대한기계학회논문집B
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    • 제37권6호
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    • pp.615-620
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    • 2013
  • 이전 연구에서 우리는 나노구조와 화학연료의 동축 구조를 제작하여 이를 점화시켰을 때, 축방향으로 매우 빠르게 화학 반응이 전파되며, 이와 동시에 높은 비출력을 가지는 화학-전기 에너지를 생성할 수 있음을 증명하였으며, 이러한 현상을 열동력 파도로 명명하였다. 본 연구에서는 열동력 파도와 관련된 여러가지 물리적인 현상을 심도있게 다루려 한다. 나노구조의 다른 배열 상태에 따라 반응 전파속도, 에너지 생성 정도가 어떻게 달라지는지, 그리고 이와 동시에 발생하는 전기 신호와는 어떤 연관 관계가 있는 지를 연구하였다. 또한 이론적으로 온도 변화에 따라 달라지는 나노튜브와 화학연료의 성질, 대류와 복사에 의한 영향을 고려했을 때 열동력 파도의 전파 양상이 어떻게 달라지는 지를 규명하였다.

로켓 모션테이블 실시간 모의시험

  • 선병찬;박용규;최형돈;조광래
    • 항공우주기술
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    • 제3권1호
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    • pp.170-178
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    • 2004
  • 본 논문은 KSR-III 개발경험을 토대로 모션테이블을 이용한 로켓 6자유도 실시간모의시험(HILS) 방안에 대해 다루고 있다. 모션테이블 HILS 시험을 통해, 3축 모션테이블의 동특성 지연에 따른 제어루프의 안정성을 판단하고 종합 HILS 시험을 위한 기초 자료를 제공하게 된다. 모션테이블 HILS 초기화 시험을 통해, 관성항법장치 초기정렬을 위한 초기자세 각 유지 알고리듬 시험, 발사시작 신호 모사를 통한 시각동기화 시험, 외부기록계를 이용한 실시간 조정시험 등을 수행하게 되고, 개루프 HILS 시험을 통해 정상 상태 비행 상황 및 슬로싱, 벤딩, TWD, 바람, 추력비정렬오차 등의 영향이 존재하는 비행 상황에 대한 모션테이블 운용 시험을 수행하게 되며, 최종적으로 모션테이블 자세각을 궤환루프의 입력으로 궤환시킨 폐루프 HILS를 통해 제어루프의 안정성 시험을 완료하게 된다.

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초음파 파워 측정 시스템 구성 및 성능평가 (Construction of Ultrasonic Power Measurement System and Its Performance Evaluation)

  • 조문재;김용태;윤용현;정성수
    • 한국음향학회지
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    • 제24권8호
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    • pp.431-440
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    • 2005
  • 초음파 파워의 정확한 측정은 초음파 의료 장비의 품질 보증과 안전성에 중요하다. 본 논문에서는 초음파 조사가 on/off를 반복하는 동안의 표적에 작용하는 방사 힘과 부력과 같은 다른 원인에서 기인하는 저울 지시 값의 시간에 따른 변화로부터 초음파 파워를 결정하는 간단한 이론을 제시하였다. 아울러 개발된 초음파 파워 측정 시스템에 대해 정밀 기계적 정렬장치, 전기신호 발생부 구성, 제어 및 측정부 구성 및 적절한 절차와 함께 상세히 기술하였다. 본 시스템으로 1 MHz, 5 MHz, 10 MHz, 15 MHz에서 10 mW에서 10 W범위에 걸쳐 측정된 결과를 다른 나라에서 교정된 기준 데이터와 상호 비교한 결과 상대 편차가 $5\%$ 이내로 확인되었다.