• Journal of Korea Multimedia Society
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• v.6 no.4
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• pp.583-593
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• 2003

Engineering design applications require the support of long transactions in cooperative environments. The problem of the existing copy/update/merge approaches is that the partial effects of a committed transaction may be not part of the merged version. This paper introduces a new cooperative transaction model, which allows updates to be progressively notified or propagated into other transactions accessing the same object. To support incremental update propagation and notification, we use the term dynamic dependency to define the intertransaction dependency relationships among all the objects checked out from the public database. Consistency in multiple copies of the same object is achieved by a two-phase delta-merge protocol. Our model provides a synchronization of cooperative updates performed in several workspaces without using locking mechanisms.

• Journal of Information Processing Systems
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• v.16 no.3
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• pp.699-717
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• 2020

Propagation time on permissionless blockchain plays a significant role in terms of stability and performance in the decentralized systems. A large number of activities are disseminated to the whole nodes in the decentralized peer-to-peer network, thus causing propagation delay. The stability of the system is our concern in the first place. The propagation delay opens up opportunities for attackers to apply their protocol. Either by accelerating or decelerating the propagation time directly without proper calculation, it brings numerous negative impacts to the entire blockchain system. In this paper, we thoroughly review and elaborate on several parameters related to the propagation time in such a system. We describe our findings in terms of data communication, transaction propagation, and the possibility of an interference attack that caused an extra propagation time. Furthermore, we present the influence of block size, consensus, and blockchain scalability, including the relation of parameters. In the last session, we remark several points associated with the propagation time and use cases to avoid dilemmas in the light of the experiments and literary works.

• Journal of Intelligence and Information Systems
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• v.15 no.1
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• pp.65-85
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• 2009

The main purpose of this paper is to propose a sophistication framework for a global manufacturing network (GMN) driven by a mother company to autonomously propagate and coordinate transaction data that are exchanged among manufacturing partners. The framework is based on conceptual fundamentals of previous research that provide a step toward ultimate successful collaboration in the supply chain and employs mobile agents for the coordination and propagation of transaction data. Maintaining the integrity of transaction data linked to a huge information web is difficult. With the sophistication functionalities of this framework, it becomes easy to effectively control the overall GMN operations and to accomplish the intended goals. The current level of sophistication focuses on the transaction data propagation. The sophistication level may be expanded up to business intelligence in the future.

• Journal of Internet Computing and Services
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• v.4 no.6
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• pp.87-93
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• 2003

Data Replication makes distributed system and database system improved in availability and performance. But it is difficult to keep strict consistency in data update. Existing algorithms keep strict consistency, but have problems of cost a great deal and delay time. It is to introduce hybrid update propagation algorithm which permits eager update for original copy and propagates lazy update for other copies. Hybrid update propagation algorithm also permits group update in ownership. This algorithm menages replica version in order to control group update consistency. Consistency and performance is improved by combining eager update and lazy update with group ownership. Simulation shows improvement of transaction throughput and response time depending on application and execution environment.

• Journal of Korea Spatial Information System Society
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• v.5 no.2 s.10
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• pp.69-82
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• 2003

Mobile transactions updating spatial objects are long transactions that update local objects of mobile clients during disconnection. Since a recovered transaction cannot read the write sets of other transactions committed before the recovery due to disconnection, the recovered transaction may conflicts with them. However, aborting of the recovered long transaction leads to the cancellation of all updates including the recovered updates. It is definitely unsuitable to cancel the recovered updates due to the conflicts. In this paper, we propose the recovery scheme to retrieve foreign conflictive objects from the write sets of other transactions for reducing aborting of a recovered transaction. The foreign conflictive objects are part of the data committed by other transactions and may conflict with the objects updated by the recovered transaction. In the scheme, since the recovered transaction can read both the foreign conflictive objects and the recently checkpoint read set, it is possible to reupdate properly the potentially conflicted objects.

• The Journal of Fisheries Business Administration
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• v.41 no.3
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• pp.79-102
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• 2010

Abalone is a primary commodity that is almost traded as live fishes. So the application of 'addition' is common in local transaction of abalone. Nevertheless, an excessive application of addition leads to some social problems. The abalone industry is one of the most rapidly growing industry in fisheries. This growth is caused by propagation of sea cage and mechanization of feeding. As a result, the abalone distributers are increased. However, the distributers have great bargaining power, so they sometimes claim excessive addition rates to aquacultural abalone producers. Difference in fitted level of the addition rates between distributers and producers cause some problems as an aversion to shipping of abalone. Also, the words about addition have not clear definition yet. So many related terminologies, for example, addition, deviation, and loss, those have different meaning are in used. And unfortunately many industry insiders use the words, 'addition', mixed with other related terminologies on transaction. The main objective of this study is to clearly define addition's meaning on the abalone transaction and to analyze the correlations between the addition and the abalone prices, outputs, and exports. Analysis results show addition negatively affects abalone prices and outputs. Furthermore, addition contributes to abalone exports negatively contrary to expectation. Such results can provide information that 'stabilization of supply and price of abalone' is realistically better method than 'increasing of additional rates' to expand abalone exports. Negative correlations between variables tell that a dictionary definition of addition, a free as seller's benevolence, is divorced from reality of abalone industry. Therefore "Loss", that means preservation in unintentional loss of abalone objects, is more suitable than "Addition" on abalone transaction.

• KNOM Review
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• v.23 no.1
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• pp.26-33
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• 2020

Bitcoin is an electronic money that does not rely on centralized institutions such as banks and financial institutions, unlike the world's paper currencies such as dollar, won, euro and yen. In Bitcoin network, a block with transaction details is generated by mining, and the message that the block has been created is broadcast to all participating nodes in a broadcasting method to secure reliability through verification. Likewise, the mining and block propagation methods in the Bitcoin network are greatly affected by the performance of the P2P network. For example, in the case of mining, the node receiving the reward for mining varies depending on whether the block is first mined in the network and the proof of mining is propagated faster. In this paper, we applied local characteristics and Round-to-Trip(RTT) measurement to solve the problems of the existing neighbor connection method and block propagation method performed in Bitcoin network. An algorithm to improve block propagation speed is presented. Through experiments, we compare the performance of the improved algorithm with the existing algorithm to verify that the overall block propagation time is reduced.

• The KIPS Transactions:PartD
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• v.10D no.4
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• pp.647-654
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• 2003

The replication of data is used to increase its availability and to improve the performance of a system. The distributed database system has to maintain both the database consistency and the replica consistency. This paper proposes an algorithm which resolves the conflict of the operations by using the mechanism based on the structure that the replicas of each data item are hierarchically organized. Each update is propagated along the tree based on the fact that the root of each data item is the primary replica in partially replicated databases. The use of a hierarchy of data may eliminate useless propagation since the propagation can be done only to sites having the replicas. In consequence, the propagation delay of updates may be reduced. By using the timestamp and a compensating transaction, our algorithm resolves the non-serializability problem caused by the conflict of operations that can happen on the way of the update propagation due to the lazy propagation. This resolution also guarantees the data consistency.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.20 no.6
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• pp.67-81
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• 2010

As wide propagation of smartphones, e-commerce with smartphones increases rapidly. Such as transfer or stock trade systems. It has prospect that most of financial companies going to offer e-commerce systems via smartphones. And e-commerce via smartphones will be increased, hence the nature of smartphone that can be used whenever, wherever. However, legislation of e-commerce in Korea does not reflect these characteristics of smartphones, because it has set standards in regular PC. So that this study is security threat and feature of smartphones considering that the current legal system will use Certificate constraints, ensuring the safety of e-commerce and install security programs for protection of users, e-commerce responsible for the accident analysis has focused on the issues presented for this improvement.

• Journal of the Korean Operations Research and Management Science Society
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• v.20 no.3
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• pp.1-16
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• 1995

Group collaborative systems are recently emerging to support a group of users engaged in common tasks such as group decision making, engineering design, group scheduling, or collaborative writing. This paper provides an change management framework for the group collaborative system to facilitate managing dependency relationship between shared objects and dependent user views, and coordinating change and propagation activities between the two in distributed computing environments. Specifically, the framework adopts an object-oriented database paradigm and presents several object constructs capturing dependency management and change notification mechanisms. First, it introduces change management mechanisms with transient shared objects and secondly, it extends them into presistent object computing environment by integrating transaction management mechanisms and change notification mechanisms. A prototype change management framework is developed on a commercial object-oriented database management system.