• Journal of KIISE:Databases
• /
• v.30 no.5
• /
• pp.521-531
• /
• 2003

Multi-level geographic data can be mainpulated by a window query such as a zoom operation. In order to handle multi-level geographic data efficiently, a spatial indexing method supporting a window query is needed. However, the conventional spatial indexing methods are not efficient to access multi-level geographic data quickly. To solve it, other a few spatial indexing methods for multi-level geographic data are known. However these methods do not support all types of multi-level geographic data. This paper presents a new efficient spatial indexing method, the MLR-tree for window query of multi-level geographic data. The MLR-tree offers both high search performance and no data redundancy. Experiments show them. Moreover, the MLR-tree supports all types of multi-level geographic data.

• ETRI Journal
• /
• v.44 no.2
• /
• pp.208-219
• /
• 2022

Crime amount prediction is crucial for optimizing the police patrols' arrangement in each region of a city. First, we analyzed spatiotemporal correlations of the crime data and the relationships between crime and related auxiliary data, including points-of-interest (POI), public service complaints, and demographics. Then, we proposed a crime amount prediction model based on 2D convolution and long short-term memory neural network (2DCONV-LSTM). The proposed model captures the spatiotemporal correlations in the crime data, and the crime-related auxiliary data are used to enhance the regional spatial features. Extensive experiments on real-world datasets are conducted. Results demonstrated that capturing both temporal and spatial correlations in crime data and using auxiliary data to extract regional spatial features improve the prediction performance. In the best case scenario, the proposed model reduces the prediction error by at least 17.8% and 8.2% compared with support vector regression (SVR) and LSTM, respectively. Moreover, excessive auxiliary data reduce model performance because of the presence of redundant information.

• Journal of Korea Spatial Information System Society
• /
• v.11 no.2
• /
• pp.89-98
• /
• 2009

As data stream is entered into system continuously and the memory space is limited, the data exceeding the memory size cannot be processed. In order to solve the problem, load shedding methods which drop a part of data to prevent exceeding the storage space have been researched. Generally, a traditional load shedding method uses random sampling with optimized rate according to data deviation. The method samples data not to distinguish those used in spatial query because the method uses only a random sampling with optimized rate according to data deviation. Therefore, the accuracy of query was reduced in u-GIS environment including spatial query. In this paper, we researched a new load shedding method improving accuracy of the query in u-GIS environment which runs spatial query and aspatial query simultaneously. The method uses a new sampling method that samples data having low probability used in query. Therefore proposed method improves spatial query accuracy and query processing speed as applying spatial filtering operation to sampling operator.

• Journal of Korean Society for Geospatial Information Science
• /
• v.25 no.1
• /
• pp.63-70
• /
• 2017

On the spatial information open platform, the national spatial data are released to provide services that the people can use freely. Recently, the demand for high quality 3D geospatial information and indoor spatial information is increasing. However, open platform is not able to provide seamless service because spatial data of indoor and outdoor are composed of different formats and storage structures. In addition, the 3D data format used in the current service does not reflect the recent changes in service environment and new technology. Therefore, in this study, we proposed new format of 3D data used in service to improve interoperability and service of open platform 3D data. The proposed format is lighter than the existing format and the rendering speed is improved.

• Journal of Korea Multimedia Society
• /
• v.5 no.4
• /
• pp.361-371
• /
• 2002

An efficient access technique is one of the most Important requirements in GIS. Using level -of-detailed data, we can access spatial data efficiently, because of no access to the fully detailed spatial data. Previous spatial access methods do not access data with level of detail efficiently. To solve it, a few spatial access methods for spatial data with level of detail, are known. However these methods support only a few kinds of data with level of detail, i.e, data through selection and simplification operations. For the effects, we propose a new spatial indexing method supporting fast searching in all kinds of data with level of detail. In the proposed method, the collection of indexes in its own level are integrated into a single index structure. Experimental results show that our method offers both no data redundancy and high search performance.

• Journal of KIISE:Software and Applications
• /
• v.26 no.9
• /
• pp.1061-1072
• /
• 1999

한 개 이상의 사이트에 공간 데이타가 중복 저장된 분산 공간 DB에서, 동시에 수행될 수 있는 긴 트랜잭션의 변경은 일관성 제어를 위해 다른 사이트에 전파되어야 한다. 이때 같은 영역의 공간 데이타를 서로 다른 사이트에서 동시에 변경할 경우, 변경 상충 문제가 발생하거나 잠금 기법에 의한 오랜 대기 시간이 초래되는 문제가 있다. 또한 공간 객체는 잠금의 대상이 아닌 공간 관련성에 의한 종속성을 가진다.이 논문은 긴 트랜잭션으로 중복된 공간 데이타를 변경할 경우 중복 제어를 위한 변경 전파와 동시성 제어 문제를 다룬다. 중복된 공간 데이타의 변경 병렬성을 향상시키기 위해 영역 잠금 및 SR-bound WRITE 잠금 기법을 제시한다. 한 사이트에서 수정하는 객체들과 다른 사이트에서 수정하는 객체들 사이에 공간 관련성에 의한 종속성이 없을 경우 병렬 수정을 허용하도록 제어하며, 공간 관련성에 의한 종속성이 있을 경우 SR-based 2PC라 불리는, 확장된 2단계 완료 프로토콜로 협동작업을 수행해서 변경 상충을 해결하는 새로운 중복 제어 기법을 설계하고 구현한다.Abstract The update of a long transaction should be propagated to the other sites for consistency control, when spatial database are replicated at multiple sites to achieve availability, reliability, and performance. When the replicated spatial data are updated at the same time, the update of one site would be conflicted with the other or a user would not be able to access the replicated spatial data under the control of locking. Two spatial objects having spatial relationships should be cooperatively updated even if there are no conflicts of locking for them.This paper deals with the issues of concurrency control and update propagation of replicated spatial data. We present the concept of region lock and SR-bound WRITE lock for enhancing the parallelism of updating the replicated spatial data. If there are no spatial relationships between one site's objets and the other's objects, parallel update would be allowed. Concurrent update of two spatial objects having spatial relationships should be propagated and cooperated by using an extended two-phase commit protocol, called spatial relationship-based 2PC.

• The KIPS Transactions:PartD
• /
• v.18D no.1
• /
• pp.57-66
• /
• 2011

Recently, the necessity of new methods of spatial data integration and analysis in CRM has been increased since it is acknowledged that about eighty percent of all data stored in corporate databases has a spatial component. But conventional CRM systems are either incapable of managing spatial data or are not user-friendly when doing so. This paper has designed and implemented spatially-enabled integration management system that can manage consistently both enterprise and spatial data through a legacy CRM system and object-oriented database and additionally support spatial analysis and map visualization for a gCRM. Through implementation, it is demonstrated that the proposed system can facilitate effectively spatial data management and analysis in a legacy CRM system.

• Journal of the Korean earth science society
• /
• v.25 no.1
• /
• pp.10-21
• /
• 2004

Recently, spatial data integration for geoscientific application has been regarded as an important task of various geoscientific applications of GIS. Although much research has been reported in the literature, quantitative assessment of the spatial interrelationship between input data layers and an integrated layer has not been considered fully and is in the development stage. Regarding this matter, we propose here, methodologies that account for the spatial interrelationship and spatial patterns in the spatial integration task, namely a multi-buffer zone analysis and a statistical analysis based on a contingency table. The main part of our work, the multi-buffer zone analysis, was addressed and applied to reveal the spatial pattern around geological source primitives and statistical analysis was performed to extract information for the assessment of an integrated layer. Mineral potential mapping using multi-source geoscience data sets from Ogdong in Korea was applied to illustrate application of this methodology.

• Spatial Information Research
• /
• v.22 no.2
• /
• pp.31-44
• /
• 2014

According to the purpose of applications, the application program will utilize the most suitable data model and 3D modeling data would be generated based on the selected data model. In these reasons, there are various data sets to represent the same geographical features. The duplicated data sets bring serious problems in system interoperability and data compatibility issues, as well in finance issues of geo-spatial information industries. In order to overcome the problems, this study proposes a spatial data fusion method using topological relationships among spatial objects in the feature classes, called Topological Relation Model (TRM). The TRM is a spatial data fusion method implemented in application-level, which means that the geometric data generated by two different data models are used directly without any data exchange or conversion processes in an application system to provide indoor LBSs. The topological relationships are defined and described by the basic concepts of IndoorGML. After describing the concepts of TRM, experimental implementations of the proposed data fusion method in 3D GIS are presented. In the final section, the limitations of this study and further research are summarized.

• Journal of the Korea Society of Computer and Information
• /
• v.23 no.4
• /
• pp.139-145
• /
• 2018

In this paper, we propose the methodology and system to show weather information to spatial system. When using the spatial information system, it is easy and convenient to show information such as target location, mission contents, enemy threats and so on. However, drawing 1-dimensional weather information on 3-dimensional space in spatial information system is hard task. To fuse data, we need to add a spatial layer including weather information to spatial layers and perform space modeling for showing weather information as spatial data in a virtual space. The virtual space is shown by receiving meteorological data and then changing in real time through weather database linkage.