• Title/Summary/Keyword: Information acquisition

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O-CDMA Code Acquisition Algorithm Based on Magnitude and Sign of Correlation Values (상관값의 크기와 부호에 기반한 O-CDMA 부호 획득 알고리즘)

  • Chong, Da-Hae;Yoon, Tae-Ung;Lee, Young-Po;Lee, Young-Yoon;Song, Chong-Han;Park, So-Ryoung;Yoon, Seok-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.6C
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    • pp.649-655
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    • 2009
  • Mean acquisition time (MAT) is the most important performance measure for code acquisition systems, where a shorter MAT implies a better code acquisition performance. Keshavarzian and Salehi proposed the multiple-shift (MS) algorithm for code acquisition in optical code division multiple access (O-CDMA) systems. Performing two steps acquisition, the MS algorithm has a shorter MAT than that of the conventional serial-search (SS) algorithm. In this paper, we propose a rapid code acquisition algorithm for O-CDMA systems. By using an efficient combination of local signals, correlation value, and the sign of correlation value, the proposed algorithm can provide a shorter MAT compared with that of the MS algorithm. The simulation results show that the proposed algorithm presents a shorter MAT than that of the MS algorithm.

Adaptive Filter Based PN Code Phase Acquisition Under Frequency Selective Rayleigh Fading Channels

  • Lee, Donghoon;Kim, Jeongchang;Cheun, Kyungwhoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.5
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    • pp.416-425
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    • 2013
  • A hybrid PN code phase acquisition system based on a least-mean-square adaptive filter, interpreted as a channel estimator is proposed and analyzed for direct-sequence spread-spectrum systems under frequency selective Rayleigh fading channels. Closed form expressions are derived for the filter tap weights and detection/false alarm probabilities. Compared to previously proposed systems, the proposed system achieves smaller mean acquisition times, is more robust to the operating signal-to-noise ratio and allows for multiplication free tap weight updates.

The control signal construction for multi channel X-ray detector signal acquisition (다채널 X-선 검출기 신호 획득을 위한 제어 신호 구성)

  • Yi, Yun;Kim, Sung-Won;Lee, Sun-Wha;Seo, Min-Seog;Lee, Hyun-Woo;Moon, Seon-Ho;Han, Bum-Soo;Kim, In-Soo
    • Proceedings of the IEEK Conference
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    • 2003.07c
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    • pp.2839-2842
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    • 2003
  • The paper is proposed for control signals to operate X-ray detector signal acquisition system There are control signals and synchronized signals for data acquisition system. X-ray detector signal acquisition system is divided into pre-treatment part which is to amplify acquired dual 16 channel analog input, converter pan which is to multiplex, and convert data and transmit part that combine transferred data output and address in order. It also describes detailed control signals.

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Development of Remote Control Ship for Acquisition of Underwater Information (수중정보 획득을 위한 무인원격선체 개발)

  • Choi, Byoung-Gil;Cho, Gwang-Hee
    • Journal of Korean Society for Geospatial Information Science
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    • v.16 no.3
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    • pp.65-69
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    • 2008
  • This study is aimed to develope a remote control ship for acquisition of various underwater information. Remote control ship equipped with GPS, echosounder, sidescan sonar, subbottom profiler. Remote control ship is an automatic system for acquisition of inland water and coast information. For the development of remote control ship, underwater information acquisition of reservoir, dam, polluted area is expected. Also, multibeam echosounder, image sensor, water analysis sensor, etc. could be equipped in one ship. So robot-ship will be applied for the most part of industry managing water resources and preventing the flood by making bed topographic map and estimating water volumes.

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A Study on the Active Location Acquisition Terminal Using Base-station Location Information and GPS Module (기지국 위치정보와 GPS 모듈을 이용한 능동형 위치획득 단말 연구)

  • Ha, Seung-Il;Lee, Hyun-Jae;Oh, Chang-Heon
    • Journal of Digital Contents Society
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    • v.9 no.3
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    • pp.483-490
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    • 2008
  • In this paper, we propose an active location acquisition terminal needing to construct an infrastructure based on a LBS and analyze the performance in real field. The proposed terminal is compounded with a GPS module and a CDMA module, so it can get the location information independently using satellite GPS signal and the proposed terminal can decide a user location with the location information of a base station in satellite GPS shadowed area. This is the distinguishable location acquisition method from the conventional A-GPS, and it complements a disadvantage of the conventional GPS. From these results, we can confirm that the proposed active location acquisition terminal is suitable to the requirements for the LBS which are the independent location acquisition ability, the continuity in the location information acquisition and the maintenance in the location information security.

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IDEF0 Models of the FCIM System for CALS Implementation (CALS구현을 위한 FCIM 시스템의 IDEF0 모델)

  • 김중인
    • The Journal of Society for e-Business Studies
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    • v.1 no.2
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    • pp.117-131
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    • 1996
  • This paper presents the results of the systems analysis for the FCIM (Flexible Computer Integrated Manufacturing) system at the U.S. Tobyhanna Army Repair Depot, which is one of the RAMP (Rapid Acquisition of Manufactured Part) program sites for CALS implementation in the U.S. military. The FCIM system's acquisition and supply processes are represented by IDEFO function models and FCIM information systems are briefly decribed in this paper. The models presented here can be used at a reference for the development of CALS acquisition and supply systems. In addition. the distinction between input and control information on the IDEFO model it suggested from the practical modeling viewpoint.

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Design of data acquisition system for strapdown inertial navigation system (스트랩다운 관성항법 시스템을 위한 데이타 취득 시스템의 구성)

  • 조현진;김용관;정연태;이만형
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.33-38
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    • 1989
  • This paper is about construction of Data Acquisition System for Gyro-System which obtains the information such as position, velocity, acceleration and attitude etc of Dynamic Vehicle System. We made up the Data Acquisition System using IBM-PC and in connection with CYBER 180-830 based on rate table, controller and IEEE 488 Interface etc.

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A Study on the Barriers of Researcher's Access to Information (경보접근 장애요소의 심각도와 심각도 구성요인 간의 관계)

  • Lee Eun Chul
    • Journal of the Korean Society for Library and Information Science
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    • v.23
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    • pp.165-205
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    • 1992
  • The purpose of this research is to verify the hypothesis that the serious ness of barriers may have significant relevance to barrier components expressing the extent of barrier, e. g. their frequency of occurrence, effect of the barrier on the acquisition of information and on the research project and trend of the barrier. Major conclusions made in this research are summarized as follows: 1. Barriers that their frequency of occurrence are high, show high seriousness of barriers. This indicates that frequency of barriers affects the seriousness of barriers. 2. Barriers that their effects on the acquisition of information and on the research project are large, show high seriousness of barriers. This indicates that the effect of the barrier on the acquisition of information and on the research project affects the seriousness of barriers. 3. Barriers that their trends are increasing, show high seriousness of barriers. This indicates that the trend of the barrier affects the seriousness of barriers.

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Design and Construction Strategy for Disaster and Safety Record Information Resources Archives Based on Automatic Acquisition (자동수집 기반 재난안전 기록정보자원 아카이브 설계 및 구축전략)

  • Han, Hui Jeong;Gang, Ju-Yeon;Kim, Yong;Oh, Hyo-Jung
    • Journal of Korean Society of Archives and Records Management
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    • v.17 no.4
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    • pp.127-154
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    • 2017
  • Large-scale and complex disasters have frequently occurred all over the world recently, and they are repeated every year. Accordingly, the need for the systematic management and utilization of raw-data and processing information in the past has increased. For this purpose, this study proposed a construction strategy for disaster and safety record information resources archives based on automatic acquisition, which can be used as a hub for disaster and safety information. Based on local and foreign case studies, several consideration factors for building the archives are determined. Finally, this study proposed four steps for constructing the archives. These are as follows: 1) complete enumeration survey of the disaster and safety record information resources, 2) automatic acquisition possibility study, 3) selection of the resources for preservation, and 4) automatic acquisition of metadata. The construction of the archives proposed in this study will facilitate integrated management, sharing, and use of scattered information resources on disaster and safety.