• 제목/요약/키워드: Polytechnic college

검색결과 1,210건 처리시간 0.029초

A Novel Ginsenosidase from an Aspergillus Strain Hydrolyzing 6-O-Multi-Glycosides of Protopanaxatriol-Type Ginsenosides, Named Ginsenosidase Type IV

  • Wang, Dong-Ming;Yu, Hong-Shan;Song, Jian-Guo;Xu, Yu-Feng;Liu, Chun-Ying;Jin, Feng-Xie
    • Journal of Microbiology and Biotechnology
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    • 제21권10호
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    • pp.1057-1063
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    • 2011
  • Herein, a novel ginsenosidase, named ginsenosidase type IV, hydrolyzing 6-O-multi-glycosides of protopanaxatriol-type ginsenosides (PPT), such as Re, R1, Rf, and Rg2, was isolated from the Aspergillus sp. 39g strain, purified, and characterized. Ginsenosidase type IV was able to hydrolyze the 6-O-${\alpha}$-L-($1{\rightarrow}2$)-rhamnoside of Re and the 6-O-${\beta}$-D-($1{\rightarrow}2$)-xyloside of R1 into ginsenoside Rg1. Subsequently, it could hydrolyze the 6-O-${\beta}$-D-glucoside of Rg1 into F1. Similarly, it was able to hydrolyze the 6-O-$_{\alpha}$-L-($1{\rightarrow}2$)-rhamnoside of Rg2 and the 6-O-${\beta}$-D-($1{\rightarrow}2$)-glucoside of Rf into Rh1, and then further hydrolyze Rh1 into its aglycone. However, ginsenosidase type IV could not hydrolyze the 3-O- or 20-O-glycosides of protopanaxadiol-type ginsenosides (PPD), such as Rb1, Rb2, Rb3, Rc, and Rd. These exhibited properties are significantly different from those of glycosidases described in Enzyme Nomenclature by the NC-IUBMB. The optimal temperature and pH for ginsenosidase type IV were $40^{\circ}C$ and 6.0, respectively. The activity of ginsenosidase type IV was slightly improved by the $Mg^{2+}$ ion, and inhibited by $Cu^{2+}$ and $Fe^{2+}$ ions. The molecular mass of the enzyme, based on SDS-PAGE, was noted as being approximately 56 kDa.

레이저 스펙클을 이용한 진동분석 (Vibration Analysis Using Laser Speckle)

  • 육도진;성덕용;강성수;이원진
    • 한국안광학회지
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    • 제6권2호
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    • pp.77-80
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    • 2001
  • 본 논문은 저출력 He-Ne 레이저의 스펙클 현상을 이용하여, 진동하는 물체의 표면요소들에 의한 운동상태를 분석하는데 그 목격이 있다. 레이저에서 나온 빛은 구리판에서 반사되어 진동판에 스펙클로 나타난다. 이것을 뒤에 설치된 스피커의 음파로 진동시키면 스펙클은 여러 가지 형태로 변화한다. 진동판이 최대로 진동할 때의 진동수는 역학적 공명 진동수이므로 그때의 스펙클변화를 진동판에 표시한다. 스펙클은 진동하는 부분과 진동하지 않는 부분으로 나뉘어 지는데 진동하는 부분은 흐려지거나 스펙클이 나타나지 않는다. 진동모드의 변화는 진동판의 종류와 크기, 고정단 집게의 위치에 따라 달라지는 것을 볼 수 있다.

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Effect of activator types on cement mortar with polymeric aluminum chloride waste residue

  • Ping Xu;Yuhao Cui;Dong Han;Minxia Zhang;Yahong Ding
    • Advances in concrete construction
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    • 제15권3호
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    • pp.149-159
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    • 2023
  • Water glass (WG) and sodium sulfate (SS) were used to prepare polymeric aluminum chloride residue cement mortar (PACRM) by single and compound blending with polymeric aluminum chloride waste residue, respectively. The structural strength and textural characteristics examinations showed that PACRM consistency increased by incorporating WG, but decreased by incorporating SS. When WG and SS were compounded, the mortar consistency initially rose before falling. The compressive strength of PACRM increased and then decreased as WG was increased. The mechanical properties of PACRM were better enhanced by SS than WG, showing no strength deterioration. The main reason for the improved mechanical properties of polymeric aluminum chloride waste residue in the presence of activators is the increased precipitation of reactive substances, such as C-S-H gels, calcium silica, and Ca(OH)2. The density of the specimens with PACRM and the degree of aggregation of hydration products were significantly enhanced by generating more hydration products in the mortar. Further, the cracks and pores were significantly reduced, and the matrix structure was continuous and dense at 5% SS doping and 3% compound doping.

Enhancing Location Privacy through P2P Network and Caching in Anonymizer

  • Liu, Peiqian;Xie, Shangchen;Shen, Zihao;Wang, Hui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제16권5호
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    • pp.1653-1670
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    • 2022
  • The fear that location privacy may be compromised greatly hinders the development of location-based service. Accordingly, some schemes based on the distributed architecture in peer-to-peer network for location privacy protection are proposed. Most of them assume that mobile terminals are mutually trusted, but this does not conform to realistic scenes, and they cannot make requirements for the level of location privacy protection. Therefore, this paper proposes a scheme for location attribute-based security authentication and private sharing data group, so that they trust each other in peer-to-peer network and the trusted but curious mobile terminal cannot access the initiator's query request. A new identifier is designed to allow mobile terminals to customize the protection strength. In addition, the caching mechanism is introduced considering the cache capacity, and a cache replacement policy based on deep reinforcement learning is proposed to reduce communications with location-based service server for achieving location privacy protection. Experiments show the effectiveness and efficiency of the proposed scheme.

카페와 음식점의 사용자 출입 관리를 위한 단시간 얼굴 학습을 통한 얼굴 인식 시스템 구현 (Implement of Face Recognition using Short Time Face Train for User Access Management of Cafe and Restaurant)

  • 이협건;유연준;홍석민;홍두표
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2021년도 추계학술발표대회
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    • pp.808-810
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    • 2021
  • 얼굴 인식 기술들은 다양한 인공지능 플랫폼들의 발달 및 알고리즘들의 연구 개발로 인해 발전하고 있다. 대부분의 얼굴 인식 알고리즘들은 정확도를 높이기 위해 많은 양의 데이터 학습을 요구하고 잇다. 그러나 커피숍이나 음식점과 같이 사람들이 짧은 시간 머물고 있는 환경에서는 사람들의 출입 여부를 체크하기 기존의 얼굴인식 기술들을 적용함에 있어 학습량의 부족으로 부적합하다. 이에 본 논문에서 카페와 음식점의 사용자 출입 관리를 위한 단시간 얼굴 학습을 통한 얼굴 인식 시스템 구현한다. 이로 인해 카페 및 음식점의 운영자는 사용자들의 입·출입 데이터를 활용하여 테이블 회전율 분석 및 코로나19 방역수칙인 카페 2인 이상 1시간 이내 사용을 체크가 가능하다.

Recovery of Visual Strain during VDT Work

  • Muraoka, Tetsuya;Nakashima, Noboru;Takagi, Atsuo;Endo, Mikiya
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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    • pp.380-385
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    • 1998
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