• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.329-332
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• 2000

Research interests on temporal data have been almost focused on data models. There has been relatively less research in the area of temporal data management. In this paper, we propose two data migration strategies based on time-segmented storage structure: the migration strategy by Time Granularity, the migration strategy by LST-GET. We describe the criterion for data migration and moving process. We simulated the performance of the migration strategy by Time Granularity in order to compare it with non-segmentation method. We compared and analyzed two data migration strategies for temporal data.

• The Transactions of the Korea Information Processing Society
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• v.6 no.4
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• pp.851-867
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• 1999

Numerous proposals for extending the relational data model as well as conceptual and object-oriented data models have been suggested. However, there has been relatively less research in the area of defining segmented storage structure and data migration strategies for temporal data. This paper presents the segmented storage structure in order to increment search performance and the two data migration strategies for segmented storage structure. this paper presents the two data migration strategies : the migration strategy by Time granularity, the migration strategy by LST-GET. In the migration strategy by Time Granularity, the dividing time point to assign the entity versions to the past segment, the current segment, and future segment is defined and the searching and moving process for data validity at a granularity level are described. In the migration strategy by LST-GET, we describe the process how to compute the value of dividing criterion. searching and moving processes are described for migration on the future segment and the current segment and entity versions 새 assign on each segment are defined. We simulate the search performance of the segmented storage structure in order to compare it with conventional storage structure in relational database system. And extensive simulation studies are performed in order to compare the search performance of the migration strategies with the segmented storage structure.

• Journal of KIISE:Databases
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• v.28 no.3
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• pp.384-394
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• 2001

In this paper, we propose AST-AET(Average valid Start Time-Average valid End Time) data migration strategy based on the storage structure where temporal data is divided into a past segment, a current segment, and a future segment. We define AST and AET which are used in AST-AET data migration strategy and also define entity versions to be stored in each segment. We describe methods to compute AST and AET, and processes to search entity versions for migration and move them. We compare average response times for user queries between AST-AET data migration strategy and the existing LST-GET(Least valid Start Time-Greatest valid End Time) data migration strategy. The experimental results show that, when there are no LLTs(Long Lived Tuples), there is little difference in performance between the two migration strategies because the size of a current segment is nearly equal. However, when there are LLTs, the average response time of AST-AET data migration strategy is smaller than that of LST-GET data migration strategy because the size of a current segment of LST-GET data migration strategy becomes larger. In addition, when we change average interarrival times of temporal queries, generally the average response time of AST-AET data migration strategy is smaller than that of LST-GET data migration strategy.

• Journal of Korean Society of Archives and Records Management
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• v.9 no.2
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• pp.19-40
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• 2009

In this study, we proposed some fundamental considerations in application of a migration strategy for long-term preservation of electronic records. It also reviewed the notion of migration and various data migration strategies such as DPT and CAMiLEON through the literature survey.

• Journal of Korea Multimedia Society
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• v.2 no.1
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• pp.9-21
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• 1999

This paper presents the time-segmented storage structure in order to increment search performance and the two data migration strategies: migration by Time Granularity and migration by LST-GET. In the migration strategy by Time Granularity, we describe how to assign entity version to the past, current segment, and future segments. We also describe searching and moving processes for data validity at a granularity level. In the migration strategy by LST-GET, we describe how to computer the value of dividing criterion. We simulate the search performance of the proposed segmented storage structure in comparison with the conventional storage structure in comparison with the conventional storage structure in relational database system. Finally, extensive simulation studies are performed in order to compare the search performance of the migration strategies with the time-segmented storage structure.

• Current Optics and Photonics
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• v.5 no.6
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• pp.617-626
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• 2021

A parallel Monte Carlo photon migration algorithm for graphics processing units that implements an improved load-balancing strategy is presented. Conventional parallel Monte Carlo photon migration algorithms suffer from a computational bottleneck due to their reliance on a simple load-balancing strategy that does not take into account the different length of the mean free paths of the photons. In this paper, path-partition load balancing is proposed to eliminate this computational bottleneck based on a mathematical formula that parallelizes the photon path tracing process, which has previously been considered non-parallelizable. The performance of the proposed algorithm is tested using three-dimensional photon migration simulations of a human skin model.

• The Transactions of the Korea Information Processing Society
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• v.7 no.5
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• pp.1511-1519
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• 2000

Inthis paper, we present an efficient migration strategy of mobile agent for data mining application. The purpose of the proposed algorithm is to set up the best migration plan of mobile agent with regard to minimizing network execution time .In order to verify the effectiveness of the proposed algorithm, we designed a performance evaulation model for three paradigms from data mining, i.e. RPC, mobile agent and mobile agent with locker pattern, and we then evaluated the algorithm by simulation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.787-797
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• 2021

Yellowtail Seriola quinqueradiata tagged with a Pop-up Satellite Archival Tag (PSAT) was released off the coast of near the Moseulpo, Jeju Island and the ecological data during about 40 days was obtained. However, it is difficult to determine the spatial location of underwater ecological data. To improve the accuracy of estimating the Yellowtail migration route using temperature, suitable background field of the oceanic environment data was evaluated and used for input data. After developing of the tracking algorithm for migration route estimation, three experiment cases were estimated with ecological data among the surface layer, the mixed layer, and the whole water column. All tracking experiments move from western to eastern Jeju Island. Additionally, tracking experiment using 3D ocean numerical model reveal that it is possible to estimate the migration route using the fish ecological data of the entire water column. Therefore, using a large number of ecological data and a high-accuracy ocean numerical model to estimate the migration route seems to be a way to increase the accuracy of the tracking experiment. Moreover, the tracking algorithm of this study can be applied to small pelagic fishery using small archival electronic tags to track the migration route.

• Journal of Korea Society of Digital Industry and Information Management
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• v.13 no.4
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• pp.153-162
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• 2017

Advances in communication technologies and the decreasing cost of computers have made distributed computer systems an attractive alternative for satisfying the information needs of large organizations. This paper presents a distributed algorithm for performance improvement through load balancing and file migration in distributed systems. We employed a sender initiated strategy for task migration and used learning automata with several internal states for file migration. A task can be migrated according to the load information of a computer. A file is migrated to the destination processor when it is in the right boundary state. We also described an analytical model for load balancing with file migration to verify the proposed algorithm. Analytical and simulation results show that our algorithm is very well-suited for distributed system environments.

• Electronics and Telecommunications Trends
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• v.16 no.2 s.68
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• pp.73-84
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• 2001

기업용 데이터 서비스는 이제 음성, 화상, 데이터의 통합 패러다임과 전자상거래 등의 상거래 패러다임의 변화에 따라 기업의 주요 자산으로 인식되고 있다. 즉, 얼마나 기업망을 효율적으로 구성, 이용하고 또한 이를 생산 요소로 활용하느냐에 따라 기업의 생산성뿐만 아니라 수익성에도 커다란 영향을 미친다. 따라서 많은 기업 이용자들은 그들의 미래 데이터망에 대한 이전(Migration)에 신중을 기할 수밖에 없으며 이제 단순한 비용효율화 방향의 대체 서비스 모색이 아닌 기업 가치사슬상의 핵심 요소로 인식의 변화가 일고 있다. 이에 데이터 서비스 제공사업자들은 그들의 요구에 부응하는 미래 데이터 하부구조 투자와 서비스 개발을 서두르고 있으며, 이용자들의 자연스러운 Migration Path를 전략적으로 구성하고 있다. 본 고는 이용자들의 Migration 개념 변화를 고찰하고 미국 3대 사업자들의 전용회선, 프레임릴레이, ATM 서비스를 대상으로 Migration 전략을 유형화하여 비교 분석한다. 또한 이러한 분석을 통하여 국내 사업자들을 위한 전략적 시사점을 제시한다.