• Journal of KIISE:Information Networking
• /
• v.29 no.3
• /
• pp.253-264
• /
• 2002

Recently, hierarchical architectures of databases for location management have been proposed in order to accommodate the increase in user population in future personal communication systems. In particular, a 3-level hierarchical database architecture is compatible with current cellular mobile systems. In the architecture, a newly developed additional databases, regional location database(RLR), are positioned between HLR and VLRs. We propose an efficient cache scheme, called the Double T-thresholds Location Cache Scheme. The cache scheme extends the existing T-threshold location cache scheme which is competent only under 2-level architecture of location databases currently adopted by IS-41 and GSM. The idea behind our scheme is to use two pieces of cache information, VLR and RLR serving called portables. The two pieces are required in order to exploit root only locality of registration area(RA) but also locality of regional registration area(RRA) which is the wide area covered by RLR. We also use two threshold values in order to determine whether the two pieces are obsolete. In order to model the RRA residence time, the branching Eralng-$\infty$ distribution is introduced. Our minute cost analysis shows that the double T-threshold location cache scheme yields significant reduction of network and database costs for molt patterns of portables.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.59 no.6
• /
• pp.89-100
• /
• 2017

The Agricultural Policy/Environmental eXtender (APEX) model was developed to extend EPIC's capabilities of simulating land management impacts for small-medium watershed and heterogeneous farms. APEX is a flexible and dynamic tool that is capable of simulating a wide array of management practices, cropping systems, and other land uses across a broad range of agricultural landscapes. APEX have its own agricultural environmental database including operation schedule, soil property, and weather data etc., by crops. However, agriculture environmental informations the APEX model has is all based on U.S. As this can cause malfunction or improper simulation while simulating highland field. In this study, database for APEX model to be utilized for South Korea established with 44,814 agriculture fields in Pyeongchang-gun, Korea from 2007 to 2016. And assessed domestic applicability by comparing T-P unit load criteria presented by National Institution of Environmental Research and result of APEX model. As a result of APEX model simulation, average T-P value for decade was 6.18. Average T-P of every year except 2011 was in range of 5.37~10.43 and this is being involved into criteria presented by National Institution of Environmental Research. It is analyzed that adjusting slope factor can make the model applicable for domestic agricultural environment.

• Journal of Platform Technology
• /
• v.11 no.5
• /
• pp.49-58
• /
• 2023

Factory energy management system is rapidly growing and evolving due to factors such as the 3rd Basic Energy Plan and global energy cost increases, as well as environmental issues. However, implementing an essential data collection system for energy management in factory settings, which have limited space and unique characteristics, presents spatial, environmental, and energy-related challenges. This paper endeavors to mitigate these challenges by devising a data collection system implemented through an edge-based lightweight platform. A comparison and evaluation of database operation on edge devices are conducted. To conduct the evaluation, a benchmarking tool called CDI Benchmark is developed, utilizing the characteristics of existing factories involved in practical applications. The evaluation results revealed that RDBMS systems like MySQL encountered errors in the database due to high data insertion loads, making them inoperable. On the other hand, InfluxDB, thanks to its highly efficient compression algorithm, demonstrated compression rates about 6 times higher than MyRocks according to the evaluation. However, it was observed that MyRocks outperformed InfluxDB by a significant margin, recording a maximum processing time approximately 80 times faster compared to InfluxDB.

• Journal of KIISE:Databases
• /
• v.27 no.1
• /
• pp.1-12
• /
• 2000

Many object oriented database systems manage object buffers to provide fast access to objects. Traditional buffer replacement algorithms based on fixed length pages simply assume that the cost incurred by operating a buffer is propertional to the number of buffer faults. However, this assumption no longer holds in an objects buffer where objects are of variable length and the cost of replacing an object varies for each object. In this paper, we propose a cost based replacement algorithm for object buffers. The proposed algorithm replaces the have minimum costs per unit time and unit space. The cost model extends the previous page based one to include the replacement costs and the sizes of objects. The performance tests show that proposed algorithm is almost always superior to the LRU-2 algorithm and in some cases is more than twice as fast. The idea of cost based replacement can be applied to any buffer management architectures that adopt earlier algorithms. It is especially useful in object oriented database systems where there is significant variation in replacement costs.

• Journal of Korean Society of Archives and Records Management
• /
• v.19 no.1
• /
• pp.23-67
• /
• 2019

Records in Contexts (RiC) is an international archival description standard developed by integrating and normalizing four archival description standards of the International Council of Archives (ICA). RiC has the advantage of diversifying archival description, exposing the context of records, and ensuring data interoperability between disparate systems. In this study, RiC is set up as a key tool in the design of archive systems, and logical data modeling is performed to implement the database. Because of RiC's conceptual model, RiC-CM can be used as a data reference model, and which makes it possible to develop a data model that meets user requirements. Therefore, this study intends to implement these two data models: relational data model, which is widely used as the database on legacy systems, and graphical data model, which can flexibly extend objects around the relationship between information entities.

• Journal of the Korean Society of Systems Engineering
• /
• v.7 no.2
• /
• pp.7-11
• /
• 2011

A high-speed railway system represents a typical example of large-scale multi-disciplinary system, consisting of subsystems such as rolling-stock, electrical hardware, electronics, control, information, communication, civil technology etc. The system design and acquisition data of the large-scale system must be the subject under strict configuration control and management. Systems engineering technology development project for Korea next generation High-speed Electric Multiple Unit (HEMU) system in progress is a national large system development project that is not only a large-size and complex but also multi-disciplinary in nature. Therefore, all stakeholders must understand and share the functional and performance requirements of HEMU throughout its life-cycle phases. Also in the test and evaluation phase, all systems requirements must be verified. In 2011, the prototype train manufacturing will be completed. It will do test run on the commercial line and all systems requirements are verified until 2012. For the system verification, the test and evaluation process have to be established before the test trial run. Using a systems engineering tool, the system design database(SDD) with requirements traceability and development process management in the course of the development have to be established. This paper represents the test and evaluation process development based on the SEMP(Systems Engineering Management Plan) developed in the design stage. The test and evaluation process is refined and updated in comparison to the design stage one. The test and evaluation process consists of procedure, test and evaluation method and schedule. So through this process, it is defined that each systems requirements is verified on which test and about what time.

• Journal of Satellite, Information and Communications
• /
• v.12 no.1
• /
• pp.81-87
• /
• 2017

In this paper, we present the system that user can search and manage data using united interface and user can define search field dynamically. The feature of this system is that it is possible to manage multiple polymorphic meta information first. Second, there is a database integration bus that can support easy integration between the various systems. Third, it is possible to set the search item for each user which can customize polymorphism data for each user. The system studied in this paper is expected to be capable of managing big data, which is currently well received in the field of ICT. In addition, it will be possible to effectively manage multi-species polymorphic data in various fields in the future and to easily integrate between systems having various environments.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.9 no.1
• /
• pp.15-28
• /
• 1999

In Multilevel Secure Database Management System(MLS/DBMS), we assume that system has a security clearance level for each user and a classification level for each data item in system and the objective of these systems is to protect secure information from unauthorized user. Many algorithms which have been researched have focus on removing covert channel by modifying conventional lock-based algorithm or timestamp-based algorithm. but there is high-level starvation problem that high level transaction is aborted by low level transaction repeatedly. In order to solve this problem, we propose an algorithm to reduce high-level starvation using dynamic adjustment of serialization order, which is basically using orange lock. Because our algorithm is based on a single version unlike conventional secure algorithms which are performed on multiversion, it can get high degree of concurrency control. we also show that it guarantees the serializability of concurrent execution, and satisfies secure properties of MLS/DBMS.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.435-435
• /
• 2000

Light Rail Transit (LRT) system is a complex and large system in which there are many subsystems, interfaces, functions and demanding performance requirements. Because many contractors participate in the development, it is necessary to apply methods of sharing common objectives and communicating effectively among all of the stakeholders. This paper shows not only the methodology and the results of computer-aided systems engineering including requirement management, functional analysis and architecting LRT system, but also propose a tool to help manage a project by linking WBS (Work Breakdown Structure), work organization and PBS (Product Breakdown Structure). The application of computer-aided tool RDD-100 provides the capability to model product design knowledge and decisions about important issues such as architecting the top-level system. The product design knowledge will be essential in integrating the following life-cycle phase activities over the life of the LRT system. Additionally, when a new generation train system is required, the reuse of the database can increase the system design productivity and effectiveness significantly.

• Asia pacific journal of information systems
• /
• v.8 no.3
• /
• pp.1-20
• /
• 1998

We propose an Executive Information Systems (EIS) Architecture for chief officers of the Air Force using data warehousing method. This architecture has two main proposes. The one is to provide the information for chief officers to control and command their organizations effectively by analyzing operation data at normal times. The other is to provide chief officers with the information about current situation so that they may make right and rapid decisions at emergency. The architecture introduced here is one that analyzes operational trends as well as current trends in a hierarchical organization environment. System analysis and design techniques for the Air Force EIS such as data flow diagram, system structure, entity-relational diagram, and third normal form of relational database were presented. After prototype screens are demonstrated, benefits of new EIS architecture were also discussed as a conclusion.