• 한국측량학회지
• /
• 제34권6호
• /
• pp.569-578
• /
• 2016

With the recent advancement of surveying and technology, the spatial data acquisition rates and precision have been improved continually. As the updates of spatial data are rapid, and the size of data increases in line with the advancing technology, the LOD (Level of Detail) algorithm has been adopted to process data expressions in real time in a streaming format with spatial data divided precisely into separate steps. The existing GRID analysis utilizes the single DEM, as it is, in examining and analyzing all data outside the analysis area as well, which results in extending the analysis time in proportion to the quantity of data. Hence, this study suggests a method to reduce analysis time and data throughput by acquiring and analyzing DEM data necessary for GRID analysis in real time based on the area of analysis and the level of precision, specifically for streaming DEM data, which is utilized mostly for 3D geographic information service.

• 스마트미디어저널
• /
• 제12권4호
• /
• pp.47-57
• /
• 2023

육각 그리드(hexagonal grid) 구조는 지리정보시스템에서 공간정보 데이터를 처리하고 표현하기에 우수하여 많은 연구가 이루어지고 있다. 육각 그리드를 이용한 시각화는 다른 그리드 표현 방법 대비 시인성이 높지만, 이에 표현된 공간정보 데이터에 따라 양적 정보와 그리드 간 데이터 차이를 효과적으로 전달하는 데 어려움이 있다. 따라서, 본 연구에서는 육각 그리드 외곽에 그림자를 생성하여 시각적으로 육각 그리드를 강조하는 방법을 제안한다. 이를 위해 강조하고자 하는 육각 그리드들의 최외곽 선분들을 오프셋 시키고, 그 정보를 바탕으로 베지어 곡선을 생성하여 최종적인 그림자 형상을 결정한다. 그림자는 육각 그리드에서 멀어질수록 서서히 옅어진다는 특성을 활용하여, 그림자의 가장자리로 갈수록 투명도를 가변적으로 적용한다. 제안하는 방법을 이용하여 하나의 육각 그리드뿐만 아니라 여러 개의 육각 그리드가 주어지더라도 그림자 영역을 효과적으로 생성할 수 있음을 보였으며, 사용자 인터페이스의 입력에 따라 다양한 그림자 형상을 생성할 수 있다. 서울특별시의 행정구 중 용산구에 제안하는 방법을 활용하여 그림자를 생성한 후 시각적으로 강조한 결과를 보인다.

• 전기학회논문지P
• /
• 제64권2호
• /
• pp.85-91
• /
• 2015

With the increasing popularity of Smart Grid infrastructure, it is much easier to collect energy usage data using AMI (Advanced Measuring Instrument) from residential housing, buildings and factories. Several researches have been done to improve an energy efficiency by analyzing the collected energy usage data. However, it is not easy to store and analyze the energy data using a traditional relational database management system since the data size grows exponentially with an increasing popularity of Smart grid infrastructure. In this paper, we are proposing a Hadoop based Big data system to store and analyze energy usage data. Based on our limited experiments, Hadoop based energy data analysis is three times faster than that of a relational database management system based approach with the current system.

• 인터넷정보학회논문지
• /
• 제7권6호
• /
• pp.63-77
• /
• 2006

다양한 그리드 커뮤니티가 생겨나면서 그리드 환경에서의 데이터 분산 전송의 요구가 증가하고 있다. 기존 LAN 환경 또는 특수 목적 네트워크망에서는 데이터 분산 전송을 위해서 멀티캐스팅 기술을 활용하여 네트워크 트래픽을 많이 줄일 수 있었다. 하지만 전송 성능이 일반 유니캐스트 전송보다 좋지 못하고, 하드웨어 지원 없이는 일반적인 WAN 환경에서 멀티 캐스팅을 적용할 수 없다는 단점을 갖고 있어서 그리드 응용에 적용하는 데는 한계가 있다. 이러한 문제점을 극복하기 위해서 본 논문에서는 데이터 분산 전송 기법인 DDMG(Data Dissemination Mechanism for Grid)를 제안하였다. DDMG는 보다 신속한 데이터 전송을 위하여 P2P 데이터 공유 방법을 활용하였으며, 또한 Globus XIO 라이브러리를 활용하여 그리드 환경의 다양한 프로토콜을 지원하도록 설계하였다. 본 논문에서는 DDMG 기법을 구현하여 LAN 환경과 WAN 환경에서 일반 유니캐스트 전송 방법과 비교 분석하였다.

• 한국컴퓨터정보학회논문지
• /
• 제22권12호
• /
• pp.131-136
• /
• 2017

PLM(Product Lifecycle Management) is an information management system that can integrate data, processes, business systems and human resources throughout the enterprise. BOM(Bills Of Material) is key data for designing, purchasing materials, manufacturing planning and management, which is basic for product development throughout the product life cycle. In this paper, we propose the efficient system to increase the data loading speed and the processing speed when using such large BOM data. We present the performance and usability of IMDG (In Memory Data Grid) for data processing when loading large amounts of data. In the UI, using the pure web grid of JavaScript instead of the existing data loading method can be improve performance of data managing.

• Journal of Information Processing Systems
• /
• 제8권2호
• /
• pp.263-278
• /
• 2012

The data grid provides geographically distributed resources for large-scale applications. It generates a large set of data. The replication of this data in several sites of the grid is an effective solution for achieving good performance. In this paper we propose an approach of dynamic replication in a hierarchical grid that takes into account crash failures in the system. The replication decision is taken based on two parameters: the availability and popularity of the data. The administrator requires a minimum rate of availability for each piece of data according to its access history in previous periods, but this availability may increase if the demand is high on this data. We also proposed a strategy to keep the desired availability respected even in case of a failure or rarity (no-popularity) of the data. The simulation results show the effectiveness of our replication strategy in terms of response time, the unavailability of requests, and availability.

• 한국농림기상학회지
• /
• 제6권3호
• /
• pp.149-163
• /
• 2004

Evapotranspiration (ET) is a critical component of the hydrologic cycle which influences economic activities as well as the natural ecosystem. While there have been numerous studies on ET estimation for homogeneous areas using point measurements of meteorological variables, monitoring of spatial ET has not been possible at landscape - or watershed - scales. We propose a site-specific application of the land surface model, which is enabled by spatially interpolated input data at the desired resolution. Gyunggi Province of South Korea was divided into a regular grid of 10 million cells with 30m spacing and hourly temperature, humidity, wind, precipitation and solar irradiance were estimated for each grid cell by spatial interpolation of synoptic weather data. Topoclimatology models were used to accommodate effects of topography in a spatial interpolation procedure, including cold air drainage on nocturnal temperature and solar irradiance on daytime temperature. Satellite remote sensing data were used to classify the vegetation type of each grid cell, and corresponding spatial attributes including soil texture, canopy structure, and phenological features were identified. All data were fed into a standalone version of SiB2(Simple Biosphere Model 2) to simulate latent heat flux at each grid cell. A computer program was written for data management in the cell - based SiB2 operation such as extracting input data for SiB2 from grid matrices and recombining the output data back to the grid format. ET estimates at selected grid cells were validated against the actual measurement of latent heat fluxes by eddy covariance measurement. We applied this system to obtain the spatial ET of the study area on a continuous basis for the 2001-2003 period. The results showed a strong feasibility of using spatial - data driven land surface models for operational monitoring of regional ET.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
• /
• pp.66-69
• /
• 2002

This article outlines the capabilities of a viewer component called GridViewer, and proves its reusability. GridViewer was designed for the construction of the image display part of GIS or remote sensing application software, and consequently it is particularly straightforward to closely couple GridViewer with access to very large images. Displaying is performed through pyramid structure, which enables to treat very large dataset up to several gigabytes in size under the limited capability of PC. GridViewer is free from responsibility to handle various formats of raster data files by taking grid coverage, which is designed by OGC to promote interoperability between implementations done by data vendors and software vendors providing analysis and grid processing implementations. GridViewer differs from other such viewer by allowing for clients to extend its function and capability by using small set of methods originally implemented in it. We show its reusability and expandability by applying it in developing application programs performing various functions not supported originally by the GridViewer COM component.

• International Journal of Computer Science & Network Security
• /
• 제22권12호
• /
• pp.29-36
• /
• 2022

Smart grid (SG) software platforms and communication networks that run and manage the entire grid are increasingly concerned about cyber security. Characteristics of the smart grid networks, including heterogeneity, time restrictions, bandwidth, scalability, and other factors make it difficult to secure. The age-old strategy of "building bigger walls" is no longer sufficient given the rise in the quantity and size of cyberattacks as well as the sophisticated methods threat actor uses to hide their actions. Cyber security experts utilize technologies and procedures to defend IT systems and data from intruders. The primary objective of every organization's cybersecurity team is to safeguard data and information technology (IT) infrastructure. Consequently, further research is required to create guidelines and methods that are compatible with smart grid security. In this study, we have discussed objectives of of smart grid security, challenges of smart grid security, defensive cybersecurity techniques, offensive cybersecurity techniques and open research challenges of cybersecurity.

• Journal of the Korean Data and Information Science Society
• /
• 제17권2호
• /
• pp.569-579
• /
• 2006

Recently, the amount of genome sequence is increasing rapidly due to advanced computational techniques and experimental tools in the biological area. Sequence comparisons are very useful operations to predict the functions of the genes or proteins. However, it takes too much time to compare long sequence data and there are many research results for fast sequence comparisons. In this paper, we propose a hybrid grid system to improve the performance of the sequence comparisons based on the LanLinux system. Compared with conventional approaches, hybrid grid is easy to construct, maintain, and manage because there is no need to install SWs for every node. As a real experiment, we constructed an orthologous database for 89 prokaryotes just in a week under hybrid grid; note that it requires 33 weeks on a single computer.