• 제목/요약/키워드: Environment-free

검색결과 2,081건 처리시간 0.028초

A Minimalist Model of Single Molecule Spectroscopy in a Dynamic Environment Studied by Metadynamics

  • Oh, In-Rok;Lee, Eun-Sang;Jung, Youn-Joon
    • Bulletin of the Korean Chemical Society
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    • 제33권3호
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    • pp.980-986
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    • 2012
  • In this paper we develop a minimalist model of single molecule spectroscopy in a dynamic environment. Our model is based upon a lattice system consisting of a probe molecule embedded in an Ising-model like environment. We assume that the probe molecule interacts with the Ising spins via a dipole-dipole potential, and calculate free energy curves and lineshapes of the system. To investigate fluctuation behavior of the system we exploit the metadynamics sampling method. In particular, using the method, we calculate the free energy curve of magnetization of the lattice and that of the transition energy of the probe molecule. Furthermore, we compare efficiencies of three different sampling methods used; unbiased, umbrella, and metadynamics sampling methods. Finally, we explore the lineshape behavior of the probe molecule as the system undergoes a phase transition from a sub-critical and to a super-critical temperature. We show that the transition energy of a probe molecule is broadly distributed due to the heterogeneous, local environments.

BEYTrans: A Free Online Collaborative Wiki-Based CAT Environment Designed for Online Translation Communities

  • Bey, Youcef;Kageura, Kyo;Boitet, Christian
    • 한국언어정보학회:학술대회논문집
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    • 한국언어정보학회 2007년도 정기학술대회
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    • pp.87-94
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    • 2007
  • This paper introduces BEYTrans (Better Environment for Your TRANSlation), the first experimental environment for free online collaborative computer-aided translation. The requirements and functionalities related to individual translators and communities of translators are distinguished and described. These functionalities have been integrated in a Wiki-based complete environment, equipped with all currently possible asynchronous linguistic resources and translation aids. Functions provided by BEYTrans are also compared with existing CAT systems and ongoing experiments are discussed.

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해저 배관의 허용 노출길이 산정에 대한 이론해석 (Theoretical analysis for determation of allowable free span of subsea pipeline)

  • 정동호;이용두;박한일
    • 한국해양환경ㆍ에너지학회지
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    • 제6권2호
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    • pp.54-62
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    • 2003
  • 해저배관은 지반쇄굴로 인하여 일부분이 노출되어 자유경간이 형성될 수 있다. 자유경간이 형성되면 환경하중 및 와동유기진동에 의해서 안정성을 잃을 수 있다. 본 연구에서는 해저배관의 안정성을 위협하는 중요 요소인 자유경간의 정적 및 동적 경간을 결정하는 방법을 제시한다. 자유경간 해석에서는 해저배관에 작용하는 압축력 효과를 고려하였으며 토양의 종류에 따라 경계조건을 일반화시켰다. 자유경간 양단의 해저지반은 탄성기초로 간주하였으며, 이들 선형 및 회전 스프링으로 치환하여 경계조건을 일반화시켰다. 정적 및 동적 자유경간의 길이를 산정 할 수 있는 무차원화 된 곡선을 구하였다. 예제해석을 수행하여 그 적용방법을 소개하였다. 본 연구결과는 자유경간을 갖는 해저배관의 설계에 유용하게 적용될 수 있다.

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저밀도 USN 환경을 위한 Range-hybrid 기반의 향상된 이동객체 추적기법 (An Enhanced Mobile Object Tracking Method based on Range-hybrid for Low-Density USN Environment)

  • 박재복;조기환
    • 전자공학회논문지CI
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    • 제47권2호
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    • pp.54-64
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    • 2010
  • 위치측정은 사용자나 사물에게 주변 환경에 대한 인식을 가능케 하는 기본적인 요소이기 때문에 센서네트워크 환경에서는 가장 핵심적인 요소이다. 기존 위치측정 기법은 크게 Range-based방식과 Range-free방식으로 나눌 수 있다. Range-based방식은 전파의 불규칙하고 추가 장비가 필요한 반면에 Range-free방식은 능동적인 통신을 수단으로 위치를 측정하므로 자원제약적인 센서네트워크에서는 적합한 것으로 알려져 있다. 그러나 위치측정의 정확성이 주변노드의 수에 따라 크게 좌우된다. 특히 밀집도가 낮은 센서네트워크 환경에서는 위치측정의 정확성이 매우 낮다. 본 논문에서 제안된 DRTS(Distributed Range-hybrid Tracking Scheme)는 Range-based와 Range-free방식을 혼합하고 주변노드의 위치와 통신범위 및 세기정보를 최대한 활용하여 이동물체를 추적할 수 있는 기법을 제시한다. 특히 주변노드를 최대한 활용한 효율적인 위치측정기법과 제안된 EGP(Estimative Gird Points)의 예측기법을 활용하여 위치추적의 정확성을 획기적으로 개선할 수 있는 방안을 제시한다. 그리고 시뮬레이션 결과를 통해 기존 위치추적 알고리즘 보다 추적의 정확도 관점에서 제안된 기법의 성능이 우수함을 증명하였다.

휴대용 단말기 환경을 위한 Annotation 모델링 및 시스템 구현 (Annotation Modeling and System Implementation for Hand-held Environment)

  • 손원성
    • 정보교육학회논문지
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    • 제10권2호
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    • pp.219-226
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    • 2006
  • 어노테이션(annotation)은 문서에서 개인의 의견, 정리, 요약 등을 표현하기 위한 주석을 의미한다. 따라서 전자문서에서도 어노테이션은 중요하게 사용되며 특히 전자 잉크(digital inking)릉 이용한 이동 단말기 환경에서 효과적으로 사용된다. 그러나 기존 연구에서는 휴대용 단말기 환경의 단점인 적은 디스플레이 공간을 전혀 고려하지 않기 때문에 어노테이션 작성 및 활용이 매우 불편하다. 따라서 본 논문에서는 전자펜과 이동식 단말기 환경을 고려한 어노테이션 모델 및 시스템을 제안한다. 제안 어노테이션 모델은 다양한 컨텍스트(context)를 고려하고 이에 기반한 어노테이션 마크업 언어를 정의한다. 본 모델은 다양한 어노테이션 타입 및 의미(semantic) 모델, 펜 기반 어노테이션의 자동 인식 및 영역 보정 기능 등을 고려하며, 이것을 기반으로 CAML(Context-based Annotation Markup Language)를 정의한다. 또한 본 모델을 이용하여 XML 기반의 전자책문서 및 단말기 환경을 고려한 어노테이션 시스템을 구현하고 그 활용 가능성에 대하여 살펴본다. 본 연구의 결과는 eLearning, Cyber-Class, IETM(Interactive Electronic Technical Manuals) 에서 적절히 응용 가능하다.

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Phenolic compounds and antioxidant activity of berries produced in South Korea

  • Lee, Yongcheol;Lee, Jea-Kyoo;Kim, Jeong-Gon;Park, So-Hyun;Kim, Young-Eun;Park, Sung-Kyu;Kim, Moo-Sang
    • Journal of Applied Biological Chemistry
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    • 제63권4호
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    • pp.297-303
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    • 2020
  • Berries are rich sources of phenolic compounds, which are known to have health-promoting effects. In this study, phenolic compounds of seven popularly consumed berries were analyzed by HPLC-ESI-MS/MS. In addition, 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical and nitrite scavenging activities were investigated for comparison of the biological activity of the berry extracts. Chlorogenic acid was the major phenolic acid, which had the highest content in aronia, followed by blueberry. The rutin and isoquercetin contents were the highest in mulberry, followed by aronia, black raspberry, and blueberry. The anthocyanin content was the highest in black raspberry. Aronia showed the highest DPPH free radical and nitrite scavenging activities with the highest contents of total phenolics and proanthocyanidins.

교통약자용 무료 셔틀버스 실내의 물리적 환경 특성 예비연구 - 노인의 특성을 중심으로 - (A Preliminary Study on the Physical Environment Characteristics of Free Shuttle Bus Interior for Vulnerable Pedestrian. - Focusing on the Characteristics of the Elderly -)

  • 정상원;남경숙
    • 한국실내디자인학회논문집
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    • 제27권1호
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    • pp.156-164
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    • 2018
  • This study analyzed the characteristics of Physical Environment of existing free shuttle bus Interior centered on elderly people who frequently use free shuttle buses. The purpose of this study is to provide basic data that can be used for improvement of existing free shuttle buses. In the case of the old type, in terms of accessible design, the middle entrance is not normally opened except the wheelchair occupant, so that the entrance of the front wheel is always used. Therefore, most elderly people go to the back seat and travel distance is twice longer. In addition, many stairs caused frequent inconveniences for boarding. In the case of the new type, it is planned to be a low-floor type, and various types of safety rods and handles, pictograms for enhancing the information convenience are well-equipped, and the measured value of the overall design characteristic is high. However, in the case of mental stability, it was confirmed that the seat of the bus is colored with a cold color system and is in a different relationship with the warm color which can feel mental stability. Overall, both old and new shuttle buses lack audiovisual feedback on bus routes and route guidance in terms of Supportive design. Also, since the cleaning tools and other miscellaneous items were left in the room, it became an obstacle to space utilization in terms of adaptable design. In terms of safety, both shuttle buses did not come into view with fire extinguishers shaded by miscellaneous items. Therefore, immediate action is unlikely in case of emergency. This problem should be resolved quickly.

A two-dimensional positioning system by use of rotation-free mark pattern

  • Kashiwagi, Hiroshi;Sakata, Masato
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.1737-1741
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    • 1991
  • The authors proposed a new two-dimensional(2D) positioning system by use of M-array and correlation technique which is suitable for noisy environment in '88KACC and its revised versions in '89KACC and '90KACC. This system uses the property of M-array that the autocorrelation function of the M-array has a sharp peak at its origin. In this paper, a new mark pattern is developed, instead of M-array, with which the two-dimensional positioning system becomes robust to rotation error of TV camera. The property of the rotation-free pattern is checked under various conditions, and it is shown that, by use of this rotation-free pattern, the positioning system can be used not only in a noisy environment but also in a roughly aligned set up of the TV camera.

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Modeling of Groundwater Flow Using the Element-Free Galerkin (EFG) Method

  • Park, Yu-Chul;Darrel I. Leap
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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    • pp.77-80
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    • 2001
  • The element-free Galerkin (EFG) method is one of meshless methods, which is an efficient method of modeling problems of fluid or solid mechanics with complex boundary shapes and large changes in boundary conditions. This paper discusses the theory of the EFG method and its applications to modeling of groundwater flow. In the EFG method, shape functions are constructed based on the moving least square (MLS) approximation, which requires only set of nodes. The EFG method can eliminate time-consuming mesh generation procedure with irregular shaped boundaries because it does not require any elements. The coupled EFG-FEM technique was introduced to treat Dirichlet boundary conditions. A computer code EFGG was developed and tested for the problems of steady-state and transient groundwater flow in homogeneous or heterogeneous aquifers. The accuracy of solutions by the EFG method was similar to that by the FEM. The EFG method has the advantages in convenient node generation and flexible boundary condition implementation.

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