• Title/Summary/Keyword: range data

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An Approach to Estimate Daily Maximum Mixing Height(DMMH) in Pohang, Osan, and Kwangju Areas -Analysis of 10 years data from 1983 to 1992- (포항, 오산, 광주지역의 일최대 혼합고 추정 -1983~1992년의 10년간 자료의 분석-)

  • 최진수;백성옥
    • Journal of Korean Society for Atmospheric Environment
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    • v.14 no.4
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    • pp.379-385
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    • 1998
  • The Holzworth's method was applied to estimate the daily maximum mixing height (DMMH) in Pohang, Osan and Kwangju areas. The data-base were established with meteorological data collected at air bases in these areas during the period 1983∼1992. It was investigated the seasonality, monthly trends and occurrence frequencies of the estimated DMMH data in each area. The estimated mean DMMH were found in the range of 1,100 m (winter) to 1,450m (spring). These mean DMMH data showed a typical seasonality in which higher values are commonly seen during spring and fall, while lower values during summer and winter seasons. An occurrence of estimated mean DMMH which in the range of 1,000∼2,000m altitude was appeared to be about 60%.

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An Efficient Multidimensional Index Structure for Parallel Environments

  • Bok Koung-Soo;Song Seok-Il;Yoo Jae-Soo
    • International Journal of Contents
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    • v.1 no.1
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    • pp.50-58
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    • 2005
  • Generally, multidimensional data such as image and spatial data require large amount of storage space. There is a limit to store and manage those large amounts of data in single workstation. If we manage the data on parallel computing environment which is being actively researched these days, we can get highly improved performance. In this paper, we propose a parallel multidimensional index structure that exploits the parallelism of the parallel computing environment. The proposed index structure is nP(processor)-nxmD(disk) architecture which is the hybrid type of nP-nD and 1P-nD. Its node structure in-creases fan-out and reduces the height of an index. Also, a range search algorithm that maximizes I/O parallelism is devised, and it is applied to k-nearest neighbor queries. Through various experiments, it is shown that the proposed method outperforms other parallel index structures.

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Obstacle Classification for Mobile Robot Traversability using 2-dimensional Laser Scanning (2차원 레이저 스캔을 이용한 로봇의 산악 주행 장애물 판단)

  • Kim, Min-Hee;Kwak, Kyung-Woon;Kim, Soo-Hyun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.15 no.1
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    • pp.1-8
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    • 2012
  • Obstacle detection is much studied by using sensors such as laser, vision, radar and ultrasonic in path planning for UGV(Unmanned Ground Vehicle), but not much reported about its characterization. In this paper not only an obstacle classification method using 2-dimensional LMS(Laser Measurement System) but also a decision making method whether to avoid or traverse the obstacle is proposed. The basic idea of decision making is to classify the characteristics by 2D laser scanned data and intensity data. Roughness features are obtained by range data using a simple linear regression model. The standard deviations of roughness and intensity data are used as measures for decision making by comparing with those of reference data. The obstacle classification and decision making for the UGV can facilitate a short path to the target position and the survivability of the robot.

Description of Range Control System in Space Center

  • Yun, Sek-Young;Choi,Yong-Tae;Lee, Hyo-Keun
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.53.2-53
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    • 2002
  • NARO Space Center is being developed as a national project for the Korea Space Development Program. Among the major missions of the Space Center, the Range Control System is the focal point for all command and control operation of the Space Center. The acquired data from the Tracking Stations and the on-site facilities is processed and distributed in the Control Center. Data processing or data fusion is needed for the exact tracking of the Launch Vehicle from several tracking systems. The first phase, which is the best telemetry source is selected among data streams that are received from each telemetry stations using some pre-defined criterion. Trajectory data and major telemetry parameters...

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Investigation of vapor-liquid equilibrium of HFC32/134a system (HFC32/134a 계의 기-액상평형에 관한 연구)

  • Kim, C.N.;Park, Y.M.;Lee, B.K.;An, B.S.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.9 no.4
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    • pp.527-535
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    • 1997
  • Vapor-liquid equilibrium apparatus is designed and set up. The vapor-liquid equilibrium data of the binary system HFC32/134a are measured in the range between 258.15 and 283.15K at compositions of 0.2, 0.4, 0.6 and 0.8 mole fraction of HFC32. Twenty-two equilibrium data are obtained. Based upon the present data, the binary interaction parameter for Carnahan-Starling-De Santis equation of state is calculated. Temperature range of data is extended to 313.04K using the data in the open literatures. Interaction parameters are determined at nine isotherms.

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Self-healing Method for Data Aggregation Tree in Wireless Sensor Networks (무선센서네트워크에서 데이터 병합 트리를 위한 자기치유 방법)

  • Le, Duc Tai;Duc, Thang Le;Yeom, Sanggil;Zalyubovskiy, Vyacheslav V.;Choo, Hyunseung
    • Proceedings of the Korea Information Processing Society Conference
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    • 2015.04a
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    • pp.212-213
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    • 2015
  • Data aggregation is a fundamental problem in wireless sensor networks that has attracted great attention in recent years. On constructing a robust algorithm for minimizing data aggregation delay in wireless sensor networks, we consider limited transmission range sensors and approximate the minimum-delay data aggregation tree which can only be built in networks of unlimited transmission range sensors. The paper proposes an adaptive method that can be applied to maintain the network structure in case of a sensor node fails. The data aggregation tree built by the proposed scheme is therefore self-healing and robust. Intensive simulations are carried out and the results show that the scheme could adapt well to network topology changes compared with other approaches.

Design of Power Efficient Waveforms for Long Range Air-to-Air Data Links (장거리 공대공 데이터링크를 위한 저전력 웨이브폼 설계)

  • Haeuk Lee;Je Heo;Gijung Yang;Taehee Lim;Hyukjun Oh
    • Journal of Advanced Navigation Technology
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    • v.28 no.2
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    • pp.250-253
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    • 2024
  • This paper proposes a low-power waveform for a long-range air-to-air data link. In the case of an air-to-air data link, data communication is performed in the air and high Doppler shift may occur depending on the flight speed, so a waveform based on the non-coherent method is suitable. In addition, since it is mounted on an aircraft, it must have low power characteristics. This paper proposes a waveform that combines a modulation technique based on frequency modulation and pulse position modulation that can turn on/off the transmission signal. As a result of the performance analysis, it was shown that the performance was suitable for air-to-air operation while showing low power characteristics.

Enhancement on Time-of-Flight Camera Images (Time-of-Flight 카메라 영상 보정)

  • Kim, Sung-Hee;Kim, Myoung-Hee
    • 한국HCI학회:학술대회논문집
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    • 2008.02a
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    • pp.708-711
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    • 2008
  • Time-of-flight(ToF) cameras deliver intensity data as well as range information of the objects of the scene. However, systematic problems during the acquisition lead to distorted values in both distance and amplitude. In this paper we propose a method to acquire reliable distance information over the entire scene correcting each information based on the other data. The amplitude image is enhanced based on the depth values and this leads depth correction especially for far pixels.

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Design to Realtime Test Data Topic Utilize of Data Distribution Service (데이터 분산 서비스를 활용한 실시간 시험자료 토픽 설계)

  • Choi, Won-gyu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.7
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    • pp.1447-1454
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    • 2017
  • The realtime test data topic means that process for the data efficiently from many kinds of measurement device at the test range. There are many measurement devices in test range. The test range require accurate observation and determine on test object. In this realtime test data slaving framework system, the system can produce variety of test informations and all these data also must be transmitted to test information management or display system in realtime. Using RTI DDS(Data Distribution Service) middle ware Ver 5.2, we can product the efficiency of system usability and QoS(Quality of Service) requirements. So the application user enables to concentrate on applications, not middle ware. As the reason, Complex function is provided by the DDS, not the application such as Visualization Software. In this paper, I suggest the realtime test data topic on slaving framework of realtime test data based on DDS at the test range system.

Skyline Query Processing Method based on Data Centric Storage (데이터 중심 저장구조에 기반한 스카이라인 질의 처리 기법)

  • Yeo, Myung-Ho;Seong, Dong-Ook;Song, Seok-Il;Yoo, Jae-Soo
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.3-7
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    • 2009
  • Data centric storages for sensor networks have been proposed to efficiently process multi-dimensional range queries as well as exact matches. Usually, a sensor network does not process only one type of the query but supports various types of queries such as range queries, exact matches and skyline queries. Therefore, a sensor network based on a data centric storage for range queries and exact matches should process skyline queries efficiently. However, existing algorithms for skyline queries have not considered the features of data centric storages. Some of the data centric storages store similar data in sensor nodes that are placed on geographically similar locations. Consequently, all data are ordered in a sensor network. In this paper, we propose a new skyline query processing algorithm that exploits the above features of data centric storages.

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