• Journal of Korea Multimedia Society
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• v.9 no.8
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• pp.939-949
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• 2006

With the development of industry, product data management system is becoming more and more important. An expanded view of product definition function that include a bill of material and routing database, current and historical engineering data and specifications and engineering changes order history. PDM (Product Data Management) systems hold and manage such material as product specifications, plans, geometric models, CAD drawings and images. Furthermore, PDM enables companies producing complex products to spread product data in to the entire launch process. Especially, PDTnet XML Schema is an international standard for exchanging of PDM data. But PDTnet XML Schema differs from existing XML Schema in the way that its property of IDREF/IDREFS is irregular. Therefore it is important factor that. what do we use storage devices and storage techniques. We developed storage techniques and application supporting various query types and preserving PDTnet XML Schema using a relational database that guaranteeing the performance nowadays. In this paper, we will show that our storage techniques minimize repeated data and optimize query processing by using application comparison with storage techniques of existing XML Schema data.

• Journal of KIISE:Databases
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• v.30 no.1
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• pp.41-51
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• 2003

The spatiotemporal database concerns about the time-varying spatial attributes. One of the important research areas is related to the support of various location-based services in motile communication environments. It is known that database systems may be difficult to manage the accurate geometric locations of moving objects due to their continual changes of locations. However, this requirement is necessary in various spatiotemporal applications including mobile communications, traffic control and military command and control (C2) systems. In this paper we propose the $B^{st}$-tree that utilizes the concept of multi-version B-trees. It provides an indexing method (or the historical and future range query Processing on moving object's trajectories. Also we present a dynamic version management algorithm that determines the appropriate version evolution induced by the mobility patterns to keep the query performance. With experiments we .;hi)w that our indexing approach is a viable alternative in this area.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.353-356
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• 2007

With advances in sensor technology, current researches on the pertinent techniques are actively directed toward the way which enables the USN computing service. For many applications using sensor networks, the incoming data are by nature characterized as high-speed, continuous, real-time and infinite. Due to such uniqueness of sensor data characteristics, for some instances a finite-sized buffer may not accommodate the entire incoming data, which leads to inevitable loss of data, and requirement for fast processing makes it impossible to conduct a thorough investigation of data. In addition to the potential problem of loss of data, incoming data in its raw form may exhibit high degree of complexity which evades simple query or alerting services for capturing and extracting useful information. Furthermore, as traditional mining techniques are developed to handle fixed, static historical data, they are not useful and directly applicable for analyzing the sensor data. In this paper, (1) describe how three mining techniques (sensor data outlier analysis, sensor pattern analysis, and sensor data prediction analysis) are appropriate for the USN middleware structure, with their application to the stream data in ocean environment. (2) Another proposal is a middleware structure based on USN environment adaptive to above mining techniques. This middleware structure includes sensor nodes, sensor network common interface, sensor data processor, sensor query processor, database, sensor data mining engine, user interface and so on.

• Journal of KIISE:Databases
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• v.32 no.2
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• pp.129-141
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• 2005

Although spatio-temporal databases have received considerable attention recently, there has been little work on processing range sum queries on the historical records of moving objects despite their importance. Since to answer range sum queries, the direct access to a huge amount of data incurs prohibitive computation cost, materialization techniques based on existing index structures are recently suggested. A simple but effective solution is to apply the materialization technique to the MVR-tree known as the most efficient structure for window queries with spatio-temporal conditions. However, the MVR-tree has a difficulty in maintaining pre-aggregated results inside its internal nodes due to cyclic paths between nodes. Aggregate structures based on other index structures such as the HR-tree and the 3DR-tree do not provide satisfactory query performance. In this paper, we propose a new indexing technique called the Adaptive Partitioned Aggregate R-Tree (APART) and query processing algorithms to efficiently process range sum queries in many situations. Experimental results show that the performance of the APART is typically above 2 times better than existing aggregate structures in a wide range of scenarios.

• The KIPS Transactions:PartD
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• v.18D no.4
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• pp.225-236
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• 2011

Various applications of LBS (Location Based Services) are being developed to provide the customized service depending on user's location with progress of wireless communication technology and miniaturization of personalized device. To effectively process an amount of vehicles' location data, LBS requires the techniques such as vehicle observation, data communication, data insertion and search, and user query processing. In this paper, we propose the historical location index, GIP-FB (Group Insertion tree with Flexible Buffer Node) and the flexible buffer node technique to adjust the cost of data insertion and search. the designed GIP+ based index employs the buffer node and the projection storage to cut the cost of insertion and search. Besides, it adjusts the cost of insertion and search by changing the number of line segments of the buffer node with user defined time interval. In the experiment, the buffer node size influences the performance of GIP-FB by changing the number of non-leaf node of the index. the proposed flexible buffer node is used to adjust the performance of the historical location index depending on the applications of LBS.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.6
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• pp.870-875
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• 2013

After introducing diagnosis equipment power failure prevention activities for distribution system have become more active. To do facility diagnosis and maintenance work more efficiently we need to evaluate reliability for the system and should determine the priority line with appropriate criteria. Thus, to calculate risk factor for the power distribution line that are composed of many component facilities its historical failure events for the last 5 years are collected and analysed. The failure statics show that more than 60% of various failures are related to environment factors randomly and about 20% of the failures are refer to the aging. As a strategic evaluation system reflecting these environmental influence is needed, a system on the basis of the probabilistic approach related statical variables in terms of failure rate and failure probability of electrical components is proposed. The figures for the evaluation are derived from the field failure DB. With adopting Bayesian rule we can calculate easily about conditional probability query. The proposed evaluation system is demonstrated with model system and the calculated indices representing the properties of the model line are discussed.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.397-400
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• 2008

무한히 발생되는 실시간 데이터와 디스크에 저장된 히스토리컬 데이터를 동시에 처리하는 하이브리드 질의에 관한 연구가 활발히 이루어지고 있다. 하이브리드 질의는 디스크에 저장된 대용량의 공간 데이터 처리를 위해 빠른 디스크 입/출력을 요구한다. 이러한 데이터를 처리하기 위해 인덱스, 데이터 축소 기법등이 연구되었다. 데이터의 빠른 검색을 위한 인덱스 기법은 디스크에 분산 저장된 데이터에 대한 탐색 비용과 입/출력 비용을 줄이지 못한다. 또한, 샘플링을 통해 디스크 입/출력 시간 비용을 줄이는 데이터 축소 기법은 데이터의 정확성을 떨어뜨려 정확성을 요구하는 하이브리드 질의에서는 이용하기가 어렵다. 이논문에서는 디스크 입/출력 시간과 디스크 탐색 시간 비용을 줄이고, 정확성을 보장하는 과거 공간질의 처리를 위한 고속로딩 기법을 제아난다. 제안기법은 공간을 그리드 형태로 나누고 인접한 공간 데이터를 함께 관리함으로써 디스크 입/출력 비용을 줄 일 수 있다. 또한, 공간적으로 인접한 데이터를 물리적으로 인접한 곳에 저장하여 디스크 탐색시간 비용을 줄일 수 있다. 이렇게 저장된 데이터는 손실 없이 모두 저장되며, 정확성 또는 보장할 수 있다.

• The KIPS Transactions:PartA
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• v.13A no.6 s.103
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• pp.545-554
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• 2006

Although the current Web search engines provide tremendous information, it is hard to find right information among the huge information. Users need to spend extra time to filter out unnecessary information. In order to overcome the limit of current Web search engines, Semantic Web was developed to provide efficient search, integration, and reuse of information by structuring semantic information from Web resources. In this paper, an elementary education contents retrieval system using Semantic Web is proposed. The proposed system emphasizes history contents that have high relevancy among data. For construction of the proposed system, ontology is proposed first for elementary study contents and ontology for historical contents is proposed for easy access to those contents using semantic relation among them. Based on the ontology, the proposed system is designed and implemented. The proposed system has the following characteristics. First, the system provides various query formats in detail so that search results can be refined efficiently. Second, the system presents only semantically information connected with key words or including key words using study contents ontology. Finally, the proposed system can increase study effects by presenting various contents that are related with query by users.

• Journal of KIISE:Databases
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• v.27 no.1
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• pp.101-112
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• 2000

In Geographic Information System, spatial object can be changed in the attribute information, spatial location and the topological relation between them with the change of time. However traditional GIS deletes the old value of aspatial information and replaces them with new value. Therefore. it is difficult to manage thc history of changed spatial object and can not support the spatio-temporal queries including temporal queries. In this paper, we propose a spatio-temporal objected model to solve this problem. We implement the proposed model with spatio-temporal class using Gothic GIS tool. The historical information of an object is stored into the object itself for the effective history management. And, in order to provide the queries for the history of an object and spatio-temporal relationship, we add temporal operators, spatio-temporal operators, and spatio-temporal query operations into Gothic, and improve the facility of the Gothic.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.707-716
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• 2009

The role of cost modeller is to facilitate the design process by systematic application of cost factors so as to maintain a sensible and economic relationship between cost, quantity, utility and appearance which thus helps in achieving the client's requirements within an agreed budget. There are a number of research on cost estimates in the early design stage based on the improvement of accuracy or impact factors. It is common knowledge that cost estimates are undertaken progressively throughout the design stage and make use of the information that is available at each phase, through the related research up to now. In addition, Cost estimates in the early design stage shall analyze the information under the various kinds of precondition before reaching the more developed design because a design can be modified and changed in all process depending on clients' requirements. Parametric cost estimating models have been adopted to support decision making in a changeable environment, in the early design stage. These models are using a similar instance or a pattern of historical case to be constituted in project information, geographic design features, relevant data to quantity or cost, etc. OLAP technique analyzes a subject data by multi-dimensional points of view; it supports query, analysis, comparison of required information by diverse queries. OLAP's data structure matches well with multiview-analysis framework. Accordingly, this study implements multi-dimensional information system for case based quantity data related to design information that is utilizing OLAP's technology, and then analyzes impact factors of quantity by the design criteria or parameter of the same meaning. On the basis of given factors examined above, this study will generate the rules on quantity measure and produce resemblance class using clustering of data mining. These sorts of knowledge-base consist of a set of classified data as group patterns, of which will be appropriate stand on the parametric cost estimating method.