• Journal of Korea Spatial Information System Society
• /
• v.10 no.3
• /
• pp.19-30
• /
• 2008

Recently, the query processing algorithm in the field of spatial network database(SNDB) has been attracted by many Interests. But, there is little research on route-based queries. Since the moving objects move only in spatial networks, the efficient route-based query processing algorithms, like in-route nearest neighbor(IRNN), are essential for Location-based Service(LBS) and Telematics application. However, the existing IRNN query processing algorithm has a problem that it does not consider traffic jams in the road network. In this thesis, we propose an IRNN query processing algorithm which considers space restriction. Finally, we show that space-constrained IRNN query processing algorithm is efficient compared with the existing IRNN algorithm.

• The KIPS Transactions:PartD
• /
• v.8D no.1
• /
• pp.10-23
• /
• 2001

Transactions in real-time active databases have the notion of activeness where transactions are generated by external effects and another transaction. In this paper, we propose the multi version concurrency control algorithm for real-time active transactions. A real-time active transaction has a timing constraint in the form of a deadline until which the user wants to complete the transaction, and is characterized by triggering relationships which mean that association between a transaction that triggers the execution of another transaction and the triggered transaction. The triggering relationship is an important factor to resolve data conflicts among real-time active transactions. The proposed concurrency control mechanism resolves data conflicts by considering triggering relationships between conflicting transactions as well as priorities and precedence relationships. The conflict resolution mechanism considers association types of the triggering relationship such as abort and commit dependency, and then resolves data conflicts in favor of higher priority transactions. We also present the experimental results of our algorithm comparing other real-time active concurrency control algorithms.

• Journal of Korea Spatial Information System Society
• /
• v.5 no.2 s.10
• /
• pp.5-21
• /
• 2003

Sptaio-temporal databases are important to store the real-time location information of large spatio-temporal objects efficiently and retrieve them rapidly. Accordingly necessity for spatio-temporal database system that can manage spatial information, aspatial information and temporal information of spatio-temporal objects is increasing. Sptaio-temporal databases are important to store the real-time location information of large spatio-temporal objects efficiently and retrieve them rapidly. Accordingly necessity for spatio-temporal database system that can manage spatial information, aspatial information and temporal information of spatio-temporal objects is increasing. Therefore, in this paper, we propose a spatio-temporal data model that is able to efficiently manage historical spatio-temporal objects that change dynamically their states as time. Also, various spatio-temporal operations and constraint conditions are defined to keep integrity of spatio-temporal data and spatio-temporal operations.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.3
• /
• pp.53-63
• /
• 2011

Many techniques have been proposed to store and query XML data efficiently. One way achieving this goal is using relational database by transforming XML data into relational format. It is important to transform schema to preserve the content, the structure and the constraints of the semantics information of the XML document. Especially, key constraints are an important part of database theory. Therefore, the proposal technique has considered the semantics of XML as expressed by primary keys and foreign keys. And, the proposal technique can preserve not only XML data constraints but also the content and the structure and the semantics of XML data thru transformation process. Transforming information is the content and the structure of the document(the parent-child relationship), the functional dependencies, semantics of the document as captured by XML key and keyref constraints. Because of XML schema transformation ensures that preserving semantic constraints, the advantages of these transformation techniques do not need to use the stored procedure or trigger which these data ensures data integrity in the relational database. In this paper, there is not chosen the ID/IDREF key which supported in DTD, the inheritance relationship, the implicit referential integrity.

• Proceedings of the Korean Information Science Society Conference
• /
• 2004.10b
• /
• pp.454-456
• /
• 2004

데이터베이스에 대한 제약사항들은 소프트웨어의 개발 및 사용에 있어 개발자와 사용자가 모두 참고해야 하는 중요한 사항임에도 불구하고 데이터베이스 모델링괴 소프트웨어 모델링의 불일치 및 표현 방법의 차이로 인해, 일관성 있는 제약사항 명세 및 설계에 많은 어려움을 겪어왔다. OCL(Object Constraint Language)은 객체의 제약사항을 표현하는 언어로서 UML(Unified Modeling Language)의 일부분이다. 본 논문은 객체의 제악사항을 표현하는데 사용하던 OCL을 데이터베이스의 제악사항을 설계에 일관성 있게 표현, 반영하기 위하여 사용하는 기법을 제시하고, 이에 대한 검증을 수행하는 방법에 대한 연구이다. 본 논문에서는 요구사항에서 추출한 데이터베이스의 제악사항을 정의한 규칙에 따라 추출해내고, 이를 OCL의 표현법을 이용하여 정형적으로 표현한다. 그리고 그 OCL의 형식적 표현을 ODL(Object Description Language)로 정의하는 기법을 정의함으로서 이에 대한 일관성 검증을 수행하는 기법을 제안한다.

• Journal of Korea Multimedia Society
• /
• v.19 no.5
• /
• pp.881-889
• /
• 2016

Ocular region recently emerged as a new biometric trait for overcoming the limitations of iris recognition performance at the situation that cannot expect high user cooperation, because the acquisition of an ocular image does not require high user cooperation and close capture unlike an iris image. This study proposes a new method for ocular image recognition based on BRISK (binary robust invariant scalable keypoints). It uses the distance ratio of the two nearest neighbors to improve the accuracy of the detection of corresponding keypoint pairs, and it also uses geometric constraint for eliminating incorrect keypoint pairs. Experiments for evaluating the validity the proposed method were performed on MMU public database. The person recognition rate on left and right ocular image datasets showed 91.1% and 90.6% respectively. The performance represents about 5% higher accuracy than the SIFT-based method which has been widely used in a biometric field.

• Proceedings of the KIEE Conference
• /
• 2000.07a
• /
• pp.276-278
• /
• 2000

In KwangYang steel works power system operation, the ON-LINE application of power system diagnosis technology is indispensable to not only power quality, but also stable operation and economical generation. In cases of stability constraint violation. stable power system operation is obstructed. Steel works power system is consist of 154kV transmission lines, and 345, 154, 22, and 6.6[KV] distributed lines, 5 numbers of substation, 17 units of generators. For this power system operation. loadflow program is developed. Database is tied with Windows GUI application, is designed, and is interfaced with this program. This program put up with loadflow solution of assembled MMI power system, and planed to diagnose of overloads or to imitate entrance, and isolation of equipment.

• Speech Sciences
• /
• v.10 no.2
• /
• pp.35-43
• /
• 2003

General speaker verification systems improve their recognition performances by normalizing log likelihood ratio, using a speaker model and its background speaker model that are required to be verified. So these systems rely heavily on the availability of much speaker independent databases for background speaker model design. This constraint, however, may be a burden in practical and portable devices such as palm-top computers or wireless handsets which place a premium on computations and memory. In this paper, new approach for the GMM-based background model design used in portable speaker verification system is presented when the enrollment data is available. This approach is to modify three parameters of GMM speaker model such as mixture weights, means and covariances along with reduced mixture order. According to the experiment on a 20 speaker population from YOHO database, we found that this method had a promise of effective use in a portable speaker verification system.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2002.10a
• /
• pp.287-294
• /
• 2002

An automatic design method of steel frames using nonlinear analysis is developed. The geometric nonlinearity is considered by the use of stability functions. A direct search method is used as an automatic design technique. The unit value of each member is evaluated by using LRFD Interaction equation. The member with the largest unit value Is replaced one by one with an adjacent larger member selected in the database. The weight of the steel frame is taken as an objective function. Load-carrying capacities, deflections, interstory drifts, and ductility requirement are used as constraint functions. Case study of a three-dimensional two story frame are presented.

• 시스템엔지니어링워크숍
• /
• s.6
• /
• pp.126-129
• /
• 2005

Systems engineering requirement verification model developmetn for High Speed Railway systems in progress is a national large system development program that is not only large-size and complex but also multi-disciplinary in nature. For the High Speed Railway TEP development, verification requirements that could verify system function, performance, and constraint, should be derived from SSS(system Segment specification). Hereafter, this could be referred to as verification requirements. System engineering process establishes traceability between verification requirements and system requirements. These tasks could be accomplished by the schema. using computer-aided Systems Engineering tool(CORE), High Speed Railway program can become a database and other system related to High Speed Railway program will be developed effectively and efficiently.