• Proceedings of the IEEK Conference
• /
• 2003.11b
• /
• pp.3-6
• /
• 2003

In this paper, we conduct a performance analysis for the composite scheme that is obtained by combining the data distribution and the data replication schemes usually used for the implementation of distributed directory service systems. The analysis results reveal that the composite model is a viable option to overcome the performance trade-off between the data distribution and the data replication model. In this paper, we present the performance model developed for the composite model by appling queuing modelling. Using the performance model, performance values for a variety of system execution environments are suggested which enable us to bring an efficient design for high performance distributed directories.

• Journal of the Korea Society of Computer and Information
• /
• v.26 no.12
• /
• pp.159-168
• /
• 2021

Building Information Modeling (BIM) data is a digitized construction design by worldwide construction design stands rules. Some research are being conducted to utilize blockchain for safe sharing and trade of BIM data, but there is no way to store BIM data directly in the blockchain due to the size of BIM data and technical limitation of the blockchain. In this paper, we propose a method of storing BIM data by combining a distributed file system and a blockchain. We propose two network overlays for storing BIM data, and we also propose generating the Level of Detail (LOD)-based merkle tree for efficient verification of BIM data. In addition, this paper proposes a system design for distributed storage of BIM data by using blockchain besu client and IPFS client. Our system design has a result that the processing speed stably increased despite the increase in data size.

• The KIPS Transactions:PartD
• /
• v.11D no.5
• /
• pp.1143-1148
• /
• 2004

To develop multi-tier model or distributed architecture based distributed application needs to consider various aspects such as division of role between web-designer and software developer, defining entity and its usage, database connection and transaction processing etc. This paper presents DONSL(Data Server of Non SQL-Query) architecture that provides solution to above aspects through web-tier object modeling. This is the architecture that guarantees the transaction processing and performance between web-tier and DBMS through simplified usage of query logic property. This new conceptual framework also solves enterprise site implementation problems simplifying tier, and removing DAO(Data Access Object) and entity.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.10a
• /
• pp.435-437
• /
• 2016

Hadoop Distributed File System(HDFS) is a file system for distributed processing of big data by replicating data to distributed data nodes. HDFS cluster shows a great scalability up to thousands of nodes, but it assumes a exclusive node cluster with numerous nodes for the big data processing. Various operational-purpose worker systems used by office are hardly considered as a part of cluster. This paper discusses this problem and proposes a dynamic cluster management technique to increase storage capability and analytic performance of hadoop cluster. The propsed technique can add legacy systems to the cluster and can remove them from the cluster dynamically depending on their availability.

• Korean Journal of Computational Design and Engineering
• /
• v.15 no.4
• /
• pp.279-288
• /
• 2010

In this paper, a DEVS(Discrete EVent Systems Specification)-HLA(High Level Architecture) interface was developed in order to perform the simulation using the combined discrete event and discrete time simulation model architecture in a distributed environment. The developed interface connects the combined simulation model with the HLA/RTI(Run-Time Infrastructure) which is an international standard middleware for distributed simulation. The interface consists of an interface model, a model interpreter, and a distributed environment interpreter. The interface model was defined by using the combined simulation architecture in order to easily connect the existing combined simulation model without modification with the HLA/RTI. The model interpreter takes charge of data transmission between the interface model and the combined simulation model. The distributed environment interpreter takes charge of data transmission between the interface model and the HLA/RTI. To evaluate the applicability of the developed interface, it was applied to the diving simulation of a submarine in a distributed environment. The result shows that a simulation result in a distributed environment using the interface is the same to the result in a single computing environment.

• The KIPS Transactions:PartA
• /
• v.10A no.4
• /
• pp.313-320
• /
• 2003

This paper design and implements a synchronized agent mechanism that be able to synchronize SFT (Slow Frequency Transaction) data among e-business processes in distributed environment. This synchronized agent system is adopted to use mobile agent to guarantee the interoperability of the distributed processes and to solve some problems at the client/server architecture and proposes a policy to synchronize data of e-business processes on the any platforms of distributed heterogeneous systems. The proposed synchronization policy is based on the time-stamp transaction with the system priority on the unicasting transportation.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.7 no.9
• /
• pp.2134-2153
• /
• 2013

A network-coding-based scheme is proposed to improve the energy efficiency of distributed storage systems in WSNs (Wireless Sensor Networks). We mainly focus on two problems: firstly, consideration is given to effective distributed storage technology; secondly, we address how to effectively repair the data in failed storage nodes. For the first problem, we propose a method to obtain a sparse generator matrix to construct network codes, and this sparse generator matrix is proven to be the sparsest. Benefiting from this matrix, the energy consumption required to implement distributed storage is reduced. For the second problem, we designed a network-coding-based iterative repair method, which adequately utilizes the idea of re-encoding at intermediate nodes from network coding theory. Benefiting from the re-encoding, the energy consumption required by data repair is significantly reduced. Moreover, we provide an explicit lower bound of field size required by this scheme, which implies that it can work over a small field and the required computation overhead is very low. The simulation result verifies that the proposed scheme not only reduces the total energy consumption required to implement distributed storage system in WSNs, but also balances energy consumption of the networks.

• Journal of the Society of Naval Architects of Korea
• /
• v.47 no.6
• /
• pp.831-835
• /
• 2010

Currently, engineering design is carried out in a distributed manner geographically or physically. This imposes new requirements on the computational environments, such as efficient integration and collaboration in the Internet and network environments. Meanwhile, Web-based distributed design has led new paradigms in design and manufacturing fields. For example, Web-based technologies have reduced the product development time and to ensure a competitive product in order to exchange and interact of real-time design information that integrates the distributed design environment between departments as well as companies via Internet and Web. Hence, efficient data communication for design information sharing is the basis for collaborative systems in the distributed environments. Design data communication techniques such as CORBA, DCOM, and JAVA RMI have been considered in the existing research, but these techniques have some disadvantages such as limitations of interoperability and firewall problems. This paper presents the application of engineering design problems in which distributed design information resources are integrated and exchanged using Web Service for supporting XML and HTTP without interoperability and firewall problems.

• KIPS Transactions on Computer and Communication Systems
• /
• v.7 no.11
• /
• pp.275-280
• /
• 2018

The choice of a suitable distributed file system is required for loading large data and high-speed processing through subsequent applications in a cloud environment. In this paper, we propose a write performance improvement method based on GlusterFS and evaluate the performance of MapRFS, CephFS and GlusterFS among existing distributed file systems in cloud environment. The write performance improvement method proposed in this paper enhances the response time by changing the synchronization level used by the synchronous replication method from disk to memory. Experimental results show that the distributed file system to which the proposed method is applied is superior to other distributed file systems in the case of sequential write, random write and random read.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.10
• /
• pp.5156-5161
• /
• 2013

In distributed spatial data stream processing, processed tuples of downstream nodes are replicated to the upstream node in order to increase the utilization of distributed nodes and to recover the whole system for the case of system failure. However, while the data input rate increases and multiple downstream nodes share the operation result of the upstream node, the data which stores to output queues as a backup can be lost since the deletion operation delay may be occurred by the delay of the tuple processing of upstream node. In this paper, the adaptive upstream backup scheme based on operation throughput in distributed spatial data stream system is proposed. This method can cut down the average load rate of nodes by efficient spatial operation migration as it processes spatial temporal data stream, and it can minimize the data loss by fluid change of backup mode. The experiments show the proposed approach can prevent data loss and can decrease, on average, 20% of CPU utilization by node monitoring.