• Korean Management Science Review
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• v.13 no.2
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• pp.127-146
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• 1996

Integrating database views is an important step in the conceptual database design process. This paper develops a view integration support system by using a semantic object model. In order to determine the order of the integration, affinities among views and objects are analyzed by employing the vector space theory. Semantic conflicts such as naming and structural conflicts are then resolved. The resolution results are stored in a view repository. Objects and views are integrated and stored in this view repository until all views are considered. A prototype for the system is built and can be used in a client/server environment.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10a
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• pp.113-115
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• 2000

A GIS software GEO Millennium SystemTM has been developed to integrated with spatial database that combines conventional and spatially related data. As we known well the standard query language lacks the support of spatial data type and predicate, and can not serve as the query language in the spatial database directly; some extended strategies have been proposed, but some of them need their own storage manager, some introfuce new clause into the SELECT-FROM-WHERE structure, and some is very complex and available to us. So we designed our own query language on the conventional storage manager system. It supports the Spatial Data Type and predicate, and provides the full query capabilities of SQL on the non-spatial part of the database while being tightly integrated with the spatial part, without changing the standard SQL structure.

• Journal of Internet Computing and Services
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• v.7 no.5
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• pp.1-12
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• 2006

In mobile database environments, the efficient synchronization technique is required to maintain the consistency of replicated data because the same data can be replicated between so many different databases, In this paper, we propose a message digest based synchronization technique to maintain the consistency of replicated data between client databases and a server database in mobile environments. The proposed data synchronization technique has the advantage of generality aspect and extensibility aspect by using the tuple-based message digest output to detect the data conflicts.

• Journal of Korean Association for Spatial Structures
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• v.1 no.1 s.1
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• pp.135-142
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• 2001

This paper proposes structural analysis on the World Wide Web to form a part of the architectural design project. It purposes modeling space frames and a structural analysis program on the internet only by inputting basic data for forming a shape in the whole phase of space frame analysis. The analysis data is conducted by Oracle DBMS(DataBase Management System), GUI(Graphic User Internet) by Java Applet and connection with server and database by Java Servlet respectively. The result from modeling and analysis is provided as graphic and text file forms by web browsers. Programs can be executed irrespective of user's OS by using internet and highly-secured system is constructed taking advantage of Java. Of great efficiency is maintaining and recycling data as the whole is dealt by database from the beginning to the end of program.

• Journal of Korean Society of Rural Planning
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• v.20 no.4
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• pp.277-284
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• 2014

Recently the use of smart phones and mobile devices is increasing rapidly, data search and retrieval in the mobile environments are generalized. There are only few mobile applications available in the area of agriculture while huge amount of new applications are developed and uploaded. The purpose of this study was to develop the android based mobile application for providing agricultural infrastructure and disaster information. The mobile application was designed through the database establishment and management system, server management system, and mobile application development. The database is composed of weather data, agricultural infrastructure data, and agricultural disaster data. By developing the mobile application which provides agricultural infrastructure information, it is expected to improve the accessibility to agricultural information and mitigate the agricultural disaster damages.

• Journal of Internet Computing and Services
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• v.2 no.5
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• pp.41-47
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• 2001

This paper deals with an EJB-based database agent(component) used to define workflow processes, which is a core function of the e-Chautauqua workflow management system that is an on-going research product. We describe about how to design and implement the EJB-based DB agent that is deployed on EJB server as a component. The agent is located between the build-time clients and the database system, and manages database accesses, such as retrieves and stores, from the workflow definition components. Through the EJB technology, we are able to accomplish a stable database agent that can be characterized by the distributed object management, reliable recovery mechanism from system failovers, reliable large-scale transaction management, and the security functions.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.7
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• pp.3375-3400
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• 2018

With the advent of database-as-a-service (DAAS) and cloud computing, more and more data owners are motivated to outsource their data to cloud database in consideration of convenience and cost. However, it has become a challenging work to provide security to database as service model in cloud computing, because adversaries may try to gain access to sensitive data, and curious or malicious administrators may capture and leak data. In order to realize privacy preservation, sensitive data should be encrypted before outsourcing. In this paper, we present a secure and practical system over encrypted cloud data, called QSDB (queryable and secure database), which simultaneously supports SQL query operations. The proposed system can store and process the floating point numbers without compromising the security of data. To balance tradeoff between data privacy protection and query processing efficiency, QSDB utilizes three different encryption models to encrypt data. Our strategy is to process as much queries as possible at the cloud server. Encryption of queries and decryption of encrypted queries results are performed at client. Experiments on the real-world data sets were conducted to demonstrate the efficiency and practicality of the proposed system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.5
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• pp.1653-1660
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• 2010

The user information stored in database have been leaked frequently. To protect information against malevolent manager on the inside or outside aggressor, it is one of the most efficient way to encrypt information and store to database. It is better to destruct information than not to use encrypted information stored in database. The encrypted database search system is developed variously, and used widely in many fields. In this paper, we implemented the scheme that can search encrypted document without exposing user's information to the untrusted server in mobile device. We compared and analyzed the result embodied with DES, AES, and ARIA based on symmetric key by searching time.

• Geomechanics and Engineering
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• v.7 no.1
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• pp.37-53
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• 2014

A Web-based pile load test (WBPLT) system was developed and implemented in this study. Object-oriented and concept-based software design techniques were adopted to integrate the pile load test database into the system. A total of 673 case histories of pile load test were included in the database. The data consisted of drilled shaft and driven precast concrete pile axial load tests in drained, undrained, and gravel loading conditions as well as pre-analyzed data and back-calculated design parameters. Unified modeling language, a standard software design tool, was utilized to design the WBPLT system architecture with five major concept-based components. These components provide the static structure and dynamic behavior of system message flows in a visualized manner. The open-source Apache Web server is the building block of the WBPLT system, and PHP Web programming language implements the operation of the WBPLT components, particularly the automatic translation of user query into structured query language. A simple search and inexpensive query can be implemented through the Internet browser. The pile load test database is helpful, and data can be easily retrieved and utilized worldwide for research and advanced applications.

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.4
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• pp.403-411
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• 2014

In this paper, an algorithm of extracting the features of home appliances and automatically building a database to identify home appliances is designed and presented. For the verification, a software library supporting this algorithm is implemented and added to an power management system server, which was already implemented to support real-time monitoring of home appliances' power consumption status and controlling their power. The implemented system consists of a system server and clients, each of which measures the power consumed by a home appliance plugged in it and transmits the information to the server in real-time over a wireless network. Through experiments, it is verified that it is possible to identify any home appliance connected to a specific client.