• 제목/요약/키워드: retrieving

검색결과 544건 처리시간 0.027초

홀로그래픽 정보저장기기의 Pre-scan을 이용한 재생광의 각도 탐색 방법 (Retrieving Angle Searching Method using Pre-scan for Holographic Data Storage)

  • 정규일;임성용;김낙영;양현석
    • 정보저장시스템학회논문집
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    • 제7권2호
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    • pp.85-89
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    • 2011
  • In retrieving process in angle multiplexing Holographic Data Storage(HDS), It is important to search the exact recording angles. In this paper, we propose the retrieving angle searching method using pre-scan. Pre-scan method is means that rotating the galvano mirror before the retrieving process. Therefore, retrieving signals are maximized when between the galvano mirror and recoded angle are exactly matched. Through the measured signals, we will find the exact angle and compensate tangential tilt angle. The experimental results shows propose method is enough to apply the HDS.

Perception on the Use of Mobile Phones in Retrieving Information from Academic Libraries: A developing country perspective

  • Elahi, Hasinul;Islam, Shiful;Begum, Dilara
    • International Journal of Knowledge Content Development & Technology
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    • 제8권1호
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    • pp.37-50
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    • 2018
  • The purpose of the study is to identify the perception of the Library and Information Science (LIS) specialists about the use of mobile phones in retrieving information. It investigates the present status of the LIS specialists regarding mobile phone usage, perceptions regarding the use of mobile phones in retrieving information from libraries and points out the possible drawbacks and their solutions for embracing mobile phones in retrieving information from libraries and providing some suggestions. The methodology includes a quantitative approach. The authors used a survey method using a structured questionnaire to measure the perception of LIS specialists regarding the use of mobile phones in retrieving information from libraries. The findings confirmed that the majority (72%) of LIS specialists have the experience of using mobile phones for more than 10 years. Findings also indicate that the LIS specialists have agreed with the statements of advantages of using mobile phones. This paper concludes that the respondents also agreed regarding the possible advantages of introducing mobile phones in retrieving information from libraries. The paper explores the original perceptions of LIS specialists regarding the use of mobile phones in retrieving information from libraries.

Retrieving Land surface Component Temperature Using Multi-Angle Thermal Infrared Data

  • Wenjie, Fan;Xiru, Xu
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1362-1364
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    • 2003
  • As non-isothermal mixed pixel is widely existed, the pixel-mean temperature cannot adequately represent the actual thermal state of land surface. The row crop was chosen as target to discuss the problem of component temperature retrieval. At first, the matrix model was found to express the thermal radiant directionality of the target. Then correlation of multi-angle infrared radiance was analyzed. In order to increase the retrieving accuracy, we chose the retrievable parameters and established the iterative method combining with inverse matrix to retrieve component temperature. It was proved by field experiment that the method could improve the retrieving accuracy and stability remarkably.

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Some Further Consideration for the Image Retrieving of Synthetic Aperture Radiometer

  • Liu, Hao;Wu, Ji;Wu, Qiong
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1349-1351
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    • 2003
  • In this paper, theoretical channels model of Synthetic Aperture Radiometer is presented. Based on this model, how amplitude imbalance, phase imbalance and mutual coupling between the different channels effect brightness temperature image retrieving is analyzed. The computer simulation results are also presented to find out the cause of the along-track streaks usually appeared in the retrieved brightness temperature image. In addition, a new system calibration approach is introduced to solve this problem.

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구조물 전달 함수의 구성 조건 관계식에 관한 연구 (Compatibility Relationship of Transfer Function Parameters of Structures)

  • 채장범
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1994년도 추계학술대회 논문집
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    • pp.763-767
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    • 1994
  • The measured vibration on a machine or a structure is shaped by the excitation waveform and the path transfer function. Mechanism diagnostics tends to focus on retrieving source featurce by minimzing the effects of the structural path, while in structural diagnostics we are more interested in minimizing source effects and retrieving path parameters. In structural diagnostics, therefore, there are experimental issues of gathering data that are independent source effects and finding a transfer function signature that reveals structural defects. This paper describes how the transfer function can be obtained more accurately by experiment using the compatibility relationship which is newly discovered.

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근접장 홀로그램의 각도 다중화 저장 및 재생 (Recording and Retrieving of Angular Multiplexed Near-field Holograms)

  • 김경염;이병호
    • 한국광학회:학술대회논문집
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    • 한국광학회 2001년도 제12회 정기총회 및 01년도 동계학술발표회
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    • pp.60-61
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    • 2001
  • We present our experimental results on the recording and retrieving of multiplexed near-field holograms using near-field scanning optical microscopy (NSOM) and a conventional rectangular-parallelepiped or cubic photorefractive crystal. Experimental results show that we can get the angular selectivity comparable with that of the volume hologram and the retrieved spot size was smaller than the Rayleigh's limit. The results also show that the angular selectivity and the retrieved spot size are strongly dependent on the recording distance between the object and the recording medium.

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A Sketch-based 3D Object Retrieval Approach for Augmented Reality Models Using Deep Learning

  • 지명근;전준철
    • 인터넷정보학회논문지
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    • 제21권1호
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    • pp.33-43
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    • 2020
  • Retrieving a 3D model from a 3D database and augmenting the retrieved model in the Augmented Reality system simultaneously became an issue in developing the plausible AR environments in a convenient fashion. It is considered that the sketch-based 3D object retrieval is an intuitive way for searching 3D objects based on human-drawn sketches as query. In this paper, we propose a novel deep learning based approach of retrieving a sketch-based 3D object as for an Augmented Reality Model. For this work, we introduce a new method which uses Sketch CNN, Wasserstein CNN and Wasserstein center loss for retrieving a sketch-based 3D object. Especially, Wasserstein center loss is used for learning the center of each object category and reducing the Wasserstein distance between center and features of the same category. The proposed 3D object retrieval and augmentation consist of three major steps as follows. Firstly, Wasserstein CNN extracts 2D images taken from various directions of 3D object using CNN, and extracts features of 3D data by computing the Wasserstein barycenters of features of each image. Secondly, the features of the sketch are extracted using a separate Sketch CNN. Finally, we adopt sketch-based object matching method to localize the natural marker of the images to register a 3D virtual object in AR system. Using the detected marker, the retrieved 3D virtual object is augmented in AR system automatically. By the experiments, we prove that the proposed method is efficiency for retrieving and augmenting objects.

선박매매정보 추출 에이전트 시스템 구조 설계에 관한 연구 (Design for Information Retrieving Agent System for Ship Sale and Purchase)

  • 박남규
    • 한국항해항만학회지
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    • 제26권3호
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    • pp.337-344
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    • 2002
  • 선박매매사이트가 증가하고 있지만, 필요한 정보를 쉽게 찾아주는 에이전트에 관한 연구는 부족하다. 본 연구는 사이버공간상에 흩어져 있는 선박정보를 손쉽게 찾을 수 있는 지능형 에이젼트의 설계 구조를 정의하는 연구로서 Wrapper 방식의 설계기법을 사용하였다. 본 연구가 추구하고자 하는 것은 선박매매 전자상거래 시스템의 매매대상 선박을 정보추출 에이전트를 이용하여 선박정보를 선택적으로 추출, 이를 소비자에게 제공하는 선박매매용 정보추출 에이전트의 기능을 시험적으로 설계하는 것이다. 특히 본 연구는 사이버 해운거래시스템이 실현되는 환경 하에서 이를 활성화하기 방안으로 B2B 선박매매 분야에 적용하였다는 점에서 의의가 있다. 본 연구의 결과 에이전트의 프로세스는 URL 읽기, 해당 URL 원시 데이터 가져오기, 태그처리 프로세스, 패턴분석 및 분석내용 저장하기로 구성되어 있음을 파악하였다. 또한 설계전략으로 "URL페이지 읽기" 프로세스와 "소스분석" 프로세스의 연계성 정도에 따라 분리시키거나 연계시킬 수 있음을 파악하였으며, 각각의 장단점이 비교 검토되었다.

인식 행위로서 수업 담화 분석: 초등 과학 수업을 중심으로 (An Analysis of Classroom Discourse as an Epistemic Practice: Based on Elementary Science Classrooms)

  • 오필석;안유민
    • 한국초등과학교육학회지:초등과학교육
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    • 제32권3호
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    • pp.269-284
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    • 2013
  • The purpose of this study was to investigate the epistemic process in elementary science classrooms by analyzing classroom discourse as a epistemic practice. Data came from four elementary teachers in the form of video-recordings. A total of 12 elementary science lessons were examined to reveal the discursive modes and sequences in which the teacher and students participated when they constructed and developed scientific knowledge during the lessons. Three representative discursive patterns were found in the elementary science lessons explored: (i) 'Retrieving-Retrieving-${\cdots}$' by which well-established scientific knowledge was retrieved repeatedly, (ii) 'Exploring-Building on the Shared' which allowed introducing new scientific knowledge based on the scientific phenomena explored by the teacher and students together through practical work, and (iii) 'Retrieving-Elaborating/Reformulating/Narrating' or 'Building on the Shared-Elaborating/Reformulating/Narrating' which expanded and strengthened scientific knowledge already learned. These discursive patterns were suggested as discursive-epistemic mechanisms employed frequently in the epistemic process in elementary science lessons and as a basis for defining epistemic cultures of science classrooms.

위상구성행렬식을 이용한 비압축성 순환망 형태의 유로망 해석에 관한 연구 (A Study on the Analysis of Incompressible and Looped Flow Network Using Topological Constitutive Matrix Equation)

  • 유성연;김범신
    • 설비공학논문집
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    • 제22권8호
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    • pp.573-578
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    • 2010
  • Topological matrix which reflects characteristics of network connectivity has been widely used in efficient solving for complicated flow network. Using topological matrix, one can easily define continuity at each node of flow network and make algorithm to automatically generate continuity equation of matrix form. In order to analyze flow network completely it is required to satisfy energy conservation in closed loops of flow network. Fundamental cycle retrieving algorithm based on graph theory automatically constructs energy conservation equation in closed loops. However, it is often accompanied by NP-complete problem. In addition, it always needs fundamental cycle retrieving procedure for every structural change of flow network. This paper proposes alternative mathematical method to analyze flow network without fundamental cycle retrieving algorithm. Consequently, the new mathematical method is expected to reduce solving time and prevent error occurrence by means of simplifying flow network analysis procedure.