• 한국정보시스템학회지:정보시스템연구
• /
• 제6권1호
• /
• pp.159-180
• /
• 1997

Database sharing system(DBSS) refers to a system for high performance transaction processing. In DBSS, the processing nodes are locally coupled via a high speed network and share a common database at the disk level. Each node has a local memory, a separate copy of operating system, and a DBMS. To reduce the number of disk accesses, the node caches database pages in its local memory buffer. However, since multiple nodes may be simultaneously cached a page, cache consistency must be ensured so that every node can always access the latest version of pages. In this paper, we propose efficient buffer invalidation schemes in DBSS, where the database is logically partitioned using primary copy authority to reduce locking overhead. The proposed schemes can improve performance by reducing the disk access overhead and the message overhead due to maintaining cache consistency. Furthermore, they can show good performance when database workloads are varied dynamically.

• 산업경영시스템학회지
• /
• 제19권37호
• /
• pp.251-261
• /
• 1996

Databases are critical to business information systems and RDBMS is most widely used for the database system. Normalization was designed to control various anomalies(insert, update, and delete anomalies). However normalized database design does not account for the tradeoffs necessary for the performance reason. In this research, we model a database design problem without storage constraint. Given a normalized database design, in this model, we do the denormalization of duplicating columns in order in reduce frequent join processes. In this paper, we consider insert, update, delete, and storage cost, and the anomalies are treated by additional disk I/O cost necessary for each insert, update transaction. We propose a branch and bound method, and show considerable cost reduction.

• 한국도서관정보학회지
• /
• 제21권
• /
• pp.325-361
• /
• 1994

The Library of Congress' proposal to license LC MARC database and the following debate over the proposal shows that the issue on ownership of bibliographic databases, which surfaced as a topic of concern in the international library community with the OCLC's a n.0, pplication for copyright of its databases in 1982, is not fading or dead into the 1990s. In particular, the way that technological developments are outpacing the ability of the relevant organizations and legal systems to make necessary adjustments is giving the library profession a warning that cooperative efforts for further development of the international library systems, such as the UBC program, might be seriously impeded without a swift and amicable agreement on the controversial 'database ownership' issue. Here, the purpose of this paper lies in discussing the 'database ownership' issue from a macro and long-term perspective, with emphasis on its potential impacts on, and implications for, international information flows. To the end, the specific questions covered in this paper include : 1) what are the major causes of the database ownership controversy? 2) what are the potential impacts of the database ownership issue on the library profession's cooperative efforts toward free bibliographic information flows at the international level? And finally, 3) what are the implications of the database ownership issue for the Korean Library Community, which is making efforts toward the establishment of a national library network in near future through linking various library automation systems.

• 한국지능시스템학회논문지
• /
• 제3권1호
• /
• pp.65-75
• /
• 1993

Fuzzy data is a phenomenon often occurring in real life. There is the inherent vagueness of classification terms referring to a continuous scale, the uncertainty of linguistic terms such as "I almost agree" or the vagueness of terms and concepts due to the statistical variability in communication [20] and many more. Previously, such fuzzy data was approximated by non-fuzzy (crisp) data, which obviously did not lead to a correct and precise representation of the real world. Fuzzy set theory has been developed to represent and manipulate fuzzy data [18]. Explicitly managing the degree of fuzziness in databases allows the system to distinguish between what is known, what is not known and what is partially known. Systems in the literature whose specific objective is to handle imprecision in databases present various approaches. This paper is concerned with the different ways uncertainty and imprecision are handled in database design. It outlines the major areas of fuzzification in (relational) database systems.

• 정보기술과데이타베이스저널
• /
• 제6권1호
• /
• pp.103-114
• /
• 1999

Marketing decision support systems rely on an underlying enterprise information infrastructure. In traditional business situations, a limited number of product lines and markets divided into large chunks were adequately served by existing management information systems. With the advent of an increasingly segmented focus on niche markets and individual customers, the demand for market information has grown exponentially. The practical solutions offered by such data warehousing tools as OLAP and data mining directly address this need, allowing organizations to discover new niches. Marketing decision support systems built on these foundations provide organizations with new avenues for creating specifically targeted marketing strategies and promotional campaigns. The contribution of this article lies in introducing a graphical framework for data warehousing applications. Based on prior research, the framework links data warehousing and database marketing. To illustrate the effectiveness of this approach, three case examples of successful database marketing conclude the paper.

• 한국컴퓨터정보학회논문지
• /
• 제10권5호
• /
• pp.57-64
• /
• 2005

각기 다른 보안 등급을 가지고 트랜잭션을 실행하는 다중 등급 보안 데이터베이스관리시스템에서의 보안 동시성 제어 기법은 비밀통로에 대한 고려가 있어야 한다. 보안 동시성 제어에 관한 선행 연구들은 동시성 제어 과정에서의 기밀성은 보장하고 있지만 무결성과 가용성에 대한 고려를 간과하고 있다. 본 논문에서는 검증된 트랜잭션 순서 관계를 사용하여 각기 다른 보안 등급의 트랜잭션들 간에 형평성을 제공하는 보안 동시성 제어 기법을 제안한다.

• 전자통신동향분석
• /
• 제38권6호
• /
• pp.22-30
• /
• 2023

Recently, artificial intelligence has been in the spotlight across various fields. Artificial intelligence uses massive amounts of data to train machine learning models and performs various tasks using the trained models. For model training, large, high-quality data sets are essential, and database systems have provided such data. Driven by advances in artificial intelligence, attempts are being made to improve various components of database systems using artificial intelligence. Replacing traditional complex algorithm-based database components with their artificial-intelligence-based counterparts can lead to substantial savings of resources and computation time, thereby improving the system performance and efficiency. We analyze trends in the application of artificial intelligence to database systems.

• Journal of Computing Science and Engineering
• /
• 제4권2호
• /
• pp.173-187
• /
• 2010

Recent technological advances in mobile communication systems have made explosive growth in the number of mobile device users worldwide. One of the most important issues in designing a mobile computing system is location management of users. The hierarchical systems had been proposed to solve the scalability problem in location management. The scalability problem occurs when there are too many users for a mobile system to handle, as the system is likely to react slow or even get down due to late updates of the location databases. In this paper, we propose a top-down clustering algorithm for hierarchical location database systems in a wireless network. A hierarchical location database system employs a tree structure. The proposed algorithm uses a top-down approach and utilizes the number of visits to each cell made by the users along with the movement information between a pair of adjacent cells. We then present a modified algorithm by incorporating the exhaustive method when there remain a few levels of the tree to be processed. We also propose a capacity constraint top-down clustering algorithm for more realistic environments where a database has a capacity limit. By the capacity of a database we mean the maximum number of mobile device users in the cells that can be handled by the database. This algorithm reduces a number of databases used for the system and improves the update performance. The experimental results show that the proposed, top-down, modified top-down, and capacity constraint top-down clustering algorithms reduce the update cost by 17.0%, 18.0%, 24.1%, the update time by about 43.0%, 39.0%, 42.3%, respectively. The capacity constraint algorithm reduces the average number of databases used for the system by 23.9% over other algorithms.

• 한국문헌정보학회지
• /
• 제21권
• /
• pp.169-190
• /
• 1991

The purpose of this study is to investigate aspects of office information systems in japanese corporations in order to understand introduction strategies and to find out whether strategy elements could be transferred to Germany. In this study, three points of view played an important role. (a) Technological and infrastructural support systems What kind of role did the liberalization of telecommunication markets and the avaliability of computer hardware play to help develope of database industry and implement office information systems? (b) Strategies and forms of the implementation of office information system: Which strategies were successful, distribution or centralization? How were technical and organizational problems handled? (c) Process of data communication : How did the implementation of office information system change the data communication with in-house or commercial database systems? To answer these questions, this study centered around a two-step field research in Japan. (1) Screening stage: to gain a general overview of office information system in Japan. The results of this initial research have been analysed and carefully evaluated to prepare for the second and major part of field research in Japan. (2) Data collection stage: interviews with respective managers, heads offices, and data processing units in 20 enterprises. The major results of this study are as follows. Today in Japan, office information system is understood as the interconnection of the in-house and commercial database for the maximization of the use of information resource In an organization. In particular, developments in the direction of distributed systems and the 'intelligent office' by means of the new information and communication technologies are very important.

• 정보처리학회논문지B
• /
• 제14B권6호
• /
• pp.437-444
• /
• 2007

본 논문의 목적은 기존의 모션 캡쳐 기반 애니메이션을 모바일 임베디드 시스템의 적은 메모리와 낮은 계산력에 적합하게 개조하는데 있다. 모바일 임베디드 시스템의 메모리를 효율적으로 사용하기 위한 방안으로서, PC 상에서 모션 캡쳐 데이터베이스를 압축하고, 압축된 모션캡쳐 데이터베이스를 모바일 임베디드 시스템에서 조금씩 압축 해제하고 사용 직후 삭제하는 패러다임을 제안한다. 이러한 목적으로 사용될 모션 캡쳐 데이터베이스 압축 기법으로서, 다항식 정합법을 활용하여 캡쳐된 운동 랜더링 파라미터의 데이터베이스를 축소하는 방법을 제안한다. 그리고 성능향상을 위해서 다항식 정합 함수를 최적화하는 방안도 함께 제안한다. 이렇게 설계된 다항식 정합법에 기반한 데이터 압축 방식을 사용하여, 상용화된 모바일 임베디드 시스템에서 효율적인 모션 캡쳐 기반 애니메이션 제작을 시현한다.