• 제목/요약/키워드: Grid Database

검색결과 168건 처리시간 0.025초

Simulation of Grape Downy Mildew Development Across Geographic Areas Based on Mesoscale Weather Data Using Supercomputer

  • Kim, Kyu-Rang;Seem, Robert C.;Park, Eun-Woo;Zack, John W.;Magarey, Roger D.
    • The Plant Pathology Journal
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    • 제21권2호
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    • pp.111-118
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    • 2005
  • Weather data for disease forecasts are usually derived from automated weather stations (AWS) that may be dispersed across a region in an irregular pattern. We have developed an alternative method to simulate local scale, high-resolution weather and plant disease in a grid pattern. The system incorporates a simplified mesoscale boundary layer model, LAWSS, for estimating local conditions such as air temperature and relative humidity. It also integrates special models for estimating of surface wetness duration and disease forecasts, such as the grapevine downy mildew forecast model, DMCast. The system can recreate weather forecasts utilizing the NCEP/NCAR reanalysis database, which contains over 57 years of archived and corrected global upper air conditions. The highest horizontal resolution of 0.150 km was achieved by running 5-step nested child grids inside coarse mother grids. Over the Finger Lakes and Chautauqua Lake regions of New York State, the system simulated three growing seasons for estimating the risk of grape downy mildew with 1 km resolution. Outputs were represented as regional maps or as site-specific graphs. The highest resolutions were achieved over North America, but the system is functional for any global location. The system is expected to be a powerful tool for site selection and reanalysis of historical plant disease epidemics.

화일조직을 위한 인덱싱 기법의 성능 특성 비교 (Some Characteristics of the Performance in Comparison with Indexing techniques for File Organization)

  • 이구남
    • 정보교육학회논문지
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    • 제1권1호
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    • pp.49-59
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    • 1997
  • 이 논문은 자료접근 방법중 신속한 자료접근 및 갱신작업을 위해 일반적으로 많이 사용되는 인덱스(INDEX) 기법을 분석 비교함으로써 효율적인 데이타베이스 시스템을 위한 기초를 제공하고자 한다. 이를 위해 기존의 자료접근 기법들을 편의에 의해 자료 군집형태와 검출 형태에 따라 분류하고 인덱스 기법을 단일키와 다중키로 구분하였다. 단일키 인덱싱 기법을 동적 인덱스와 정적 인덱스 기법으로 나누어 비교 설명하고, 다중키 인덱스 기법중에서 K-d 트리, K-d-B 트리 및 역 화일과 그리드 화일의 자료 구조 특성을 비교 분석한 다음 각 기범들의 구조적 특성과 추출 질의어에 의한 일반적인 성능 특성을 비교 분석하였다.

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RFID/USN기반 e-Meters 시스템의 미들웨어 구현 (Implementation of e-Meters System Middleware base on RFID/USN)

  • 전원구;이명호
    • 한국항행학회논문지
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    • 제15권5호
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    • pp.729-734
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    • 2011
  • 본 논문에서는 EPCglobal에서 표준화한 미들웨어를 이용하여 e-Meters 미들웨어와 응용 프로그램을 제안하였다. EPCglobal의 표준화된 미들웨어는 SCM 및 기타 물류의 형태로 관리할 수 있도록 설계되어 있다. RFID기반을 이용한 다양한 서비스를 지원하기 위해서는 각각의 하드웨어 프로토콜을 지원할 수 있어야 한다. e-Meters 미들웨어의 주된 기능으로는 정보 상태 및 전달, 분산 데이터베이스 처리, 이벤트 발생 데이터 분석, 처리 등이 있다. e-Meter 시스템정보를 실시간으로 운영하기 위해서 데이터를 수집한 결과를 처리하는 과정까지 구성하였다.

C-HMI 기반의 원격지 중수도 설비 실시간 제어와 모니터링 구현 (Implementation of C-HMI based Real-time Control and Monitoring for Remote Wastewater Reclamation and Reusing System)

  • 이운선;박만곤
    • 전기학회논문지
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    • 제62권5호
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    • pp.717-722
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    • 2013
  • The wastewater reclamation and reusing system has been rising as an alternative of water resource exhaustion that the whole world is experiencing. In order to be able to bring about improvement of the existing wastewater reclamation and reusing system, this research has developed of Conversion-Human Machine Interaction (C-HMI) based real-time control and monitoring system such as a sensor module and gate module, web monitoring system. This system was communication almost-error-free in various environment and situation. As a result, we have achieved our goal that has to doing work correctly as a sensor and gateway module that communication error is less than 0.2% throughout the embodied system and add that it can be easily controled and configured as an interface equipment to a complex sensor of water quality. According to this, the construction of a database capable of analyzing and assessing collection, storage and various elements of reliable water quality and flow rate data can be possible.

한국의 지능형 전력동시부하율 저감시스템에 관한 연구 (A Study on Simultaneous Load Factor of Intelligent Electric Power Reduction System in Korea)

  • 김태성;이종환
    • 산업경영시스템학회지
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    • 제35권1호
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    • pp.24-31
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    • 2012
  • This study is designed to predict the overall electric power load, to apply the method of time sharing and to reduce simultaneous load factor of electric power when authorized by user entering demand plans and using schedules into the user's interface for a certain period of time. This is about smart grid, which reduces electric power load through simultaneous load factor of electric power reduction system supervision agent. Also, this study has the following characteristics. First, it is the user interface which enables authorized users to enter and send/receive such data as demand plan and using schedule for a certain period of time. Second, it is the database server, which collects, classifies, analyzes, saves and manages demand forecast data for a certain period of time. Third, is the simultaneous load factor of electric power control agent, which controls usage of electric power by getting control signal, which is intended to reduce the simultaneous load factor of electric power by the use of the time sharing control system, form the user interface, which also integrate and compare the data which were gained from the interface and the demand forecast data of the certain period of time.

이동체의 위치 정보를 저장하기 위한 해쉬 기반 색인의 성능 분석 (On the performance of the hash based indexes for storing the position information of moving objects)

  • 전봉기
    • 한국컴퓨터정보학회논문지
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    • 제11권6호
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    • pp.9-17
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    • 2006
  • 이동체 데이터베이스 시스템은 연속적으로 위치와 방향을 바꾸는 이동체 집합을 관리해야 한다. 전통적인 공간색인 기법은 정적인 공간 데이터를 관리하는 목적으로 사용되기 때문에 이동체를 위한 색인으로 부적합하다. 이동체의 위치는 연속적으로 변하기 때문에, 이동체의 색인은 변경된 위치 정보를 유지하기 위하여 빈번한 갱신 연산을 수행해야 한다. 이 논문에서는 이동체들의 이동을 처리하기 위한 삽입/삭제 비용을 분석하였다. 실험 결과에서 제안하는 동적 해싱 색인이 기존의 R-트리와 고정 그리드 보다 성능이 우수하였다.

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집중호우시 GIS를 이용한 고속도로 사면붕괴 영향평가 (GIS-based Slope Damage Assessment of Highways During Heavy Rainfalls)

  • 진상수;윤홍식;이동하;김두섭
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
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    • pp.191-198
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    • 2005
  • Slope failures during heavy rainfall have resulted in death of life and economic loss. In recent years, the research on slope damage assessment using Geographical Information System(GIS) has been actively carried out by researchers of several goverment organizations and schools. The researchers in Highway and Transportation Technology Institute (HTTI) of Korea Highway Corporation has developed the GIS database(DB), including highway, rainfalls, soil or rock geometry, types of damage, etc. and have been working on the damage assessment of highway slopes. The DB has been established and summarized in two different ways, such as highway routes and administrative districts. Grid of rainfall intensity generated by maximum rainfalls of each administrative district has been devloped. It shows good correlation of slope damage with heavy rainfalls. Most of damaged slopes were found in the amount of 100 mm to 300 mm rainfalls.

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연소파 로켓 점화기의 T형 분기관내 데토네이션파 전파 (Detonation Wave Propagation Through a T-type Branch Tube in Combustion Wave Rocket Igniter)

  • 최정열
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2003년도 제20회 춘계학술대회 논문집
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    • pp.221-224
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    • 2003
  • T-분기관을 전파하는 데토네이션 파에 대한 수치적 연구가 수행되었다. T-분기관은 데토네이션 파를 이용하여 여러 개의 연소기를 점화시키는 연소파 점화기라는 새로운 로켓 점화체계의 핵심 부분이다. Euler 방정식과 Induction parameter 방정식이 지배방정식으로 이용되었으며 반응 항은 상세 반응 기구로 얻어진 화학 반응 데이터베이스로부터 모델 되었다. 연계된 방정식의 풀이에는 2차 정확도의 내재적 시간적분과 3차 정확도의 TVD 알고리즘이 이용되었다. 2백만 개를 초과하는 격자를 이용하여 붕괴와 재 점화를 포함하는 데토네이션파의 거동을 포착할 수 있었으며, 연소파 점화기 화염관의 설계 요소를 얻었다.

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TRAO Outer Galaxy Surey in $^{13}CO$ I

  • 이영웅;김영식;강현우;정재훈;김현구;이창훈;임인성;김봉규;김광태
    • 천문학회보
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    • 제35권1호
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    • pp.65.2-65.2
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    • 2010
  • We present a result of $^{13}CO$(1-0) survey toward the Outer Galactic Plane using the multi-beam receiver system recently installed on the 14 m telescope at Taeduk Radio Astronomy Observatory(TRAO). Our first target region is from $l=108^{\circ}$ to $113^{\circ}$ and $b=-1^{\circ}$ to $+1^{\circ}$, and some extended regions are included where emission is still arising. All data are on 50" grid. Velocity resolution is 0.63 km/sec, and the total velocity range is from -150 km/sec to 100 km/sec. A total of 40,000 spectra were obtained. The rms noise is about 0.2 K per channel for unsmoothed raw data. We will present a few initial results of the survey database.

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Airflow over low-sloped gable roof buildings: Wind tunnel experiment and CFD simulations

  • Cao, Ruizhou;Yu, Zhixiang;Liu, Zhixiang;Chen, Xiaoxiao;Zhu, Fu
    • Wind and Structures
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    • 제31권4호
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    • pp.351-362
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    • 2020
  • In this study, the impact of roof slope on the flow characteristics over low-sloped gable roofs was investigated using steady computational fluid dynamics (CFD) simulations based on a k-ω SST turbulence model. A measurement database of the flow field over a scaled model of 15° was created using particle image velocimetry (PIV). Sensitivity analyses for the grid resolutions and turbulence models were performed. Among the three common Reynolds-averaged Navier-Stokes equations (RANS) models, the k-ω SST model exhibited a better performance, followed by the RNG model and then the realizable k-ε model. Next, the flow properties over the differently sloped (0° to 25°) building models were determined. It was found that the effect of roof slope on the flow characteristics was identified by changing the position and size of the separation bubbles, 15° was found to be approximately the sensitive slope at which the distribution of the separation bubbles changed significantly. Additionally, it is suggested additional attention focused on the distributions of the negative pressure on the windward surfaces (especially 5° and 10° roofs) and the possible snow redistribution on the leeward surfaces.