• Proceedings of the Korea Database Society Conference
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• 1999.10a
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• pp.25-66
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• 1999

Focus on Interoperability: There will not be consensus on hardware platforms; There will not be consensus on operating systems; There will not be consensus on network protocols; There will not be consensus on application formats. (omitted)

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.5
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• pp.390-397
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• 2013

This paper presents a consensus algorithm for uMAS (uncertain Multi-Agent Systems). Unlike previous results in which only nominal models for agents are considered, it is assumed that the uncertain agent model belongs to a known polytope set. In the middle of deriving the proposed algorithm, a convex set is found which includes all uncertainties in the problem using convexity of the polytope set. This set plays an important role in designing the consensus algorithm for uMAS. Based on the set, a consensus condition for uMAS is proposed and the corresponding consensus design problem is solved using LMI (Linear Matrix Inequality). Simulation result shows that the proposed consensus algorithm successfully leads to consensus of the state of uMAS.

• Journal of Korean Society for Quality Management
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• v.49 no.4
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• pp.527-537
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• 2021

Purpose: The purpose of this study was to suggest an improved version of Proof-of-Nonce (PoN) algorithm, which is a distributed consensus algorithm used for block chain system. Methods: First, we used response surface method for design of experiment that is to generate experimental points considering non-linear relationship among variables. Then, we employed overlapped contour plots for visualizing the impact of control variables to performance target. Results: First, we modified the consensus procedure of the existing PoN algorithm by diminishing the content of the exchanged message. Then, we verified the performance improvement of the new PoN algorithm by performing a numerical experiment and paired t-test. Finally, we established new regression models for consensus time and Transactions per second (TPS) and proposed a method for optimizing control variables for obtaining performance target. Conclusion: We could improve the performance of the previous version of PoN algorithm by modifying the content of the exchanged message during 4-steps of consensus procedure, which might be a stepping stone for designing an efficient and effective consensus algorithm for blockchain system with dynamic operation environment.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.361-366
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• 2015

The objective of this paper was to establish the attributes that determines neighbourhood satisfaction in South Africa lowincome housing subsidy scheme ultilising the Delphi approach. This is because the perception and housing satisfaction of lowincome housing beneficiaries toward their housing condition can be studied by examining their satisfaction toward s the neighbourhood factors. The Delphi method was used where the views of housing experts were solicited on 26 potential attributes as identified from li terature. Consensus was achieved after three iterative rounds. The expert"s scored each attributes on a 10-point ordinal scale of impact significance, where 1-2=No impact and 9-10= very high impact. The scales adapted for consensus were: strong consensus, median 9-10, inter quartile deviation (IQD) ≤1; good consensus, median 7 ≤ 6.99and IQD≥2.1≤3. The key findings indicate that there was a good to strong consensus of 19 attributes which were key attributes that the experts perceived as determinants of neighbourhood satisfaction; while 6 other attributes had weak consensus, as they were considered to have a le sser impact in determining residents" neighbourhood satisfaction. However, attributes with weak consensus were the attributes that are highly regarded as core neighbourhood factors in other housing settings. The study contributes to the body of knowledge on th e subject where no consensus has been reached pertaining to indicators for measuring neighbourhood satisfaction in subsidised low-income housing in South Africa.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.2
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• pp.151-157
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• 2022

In this paper, the performance of various blockchain consensus algorithms was compared and analyzed as a method to increase the transaction cost and processing time during NFT transactions and to increase the transaction stability requirements that occur during smart contract execution. Network reliability and TPS are evaluation items for performance comparison. TPS and the stability of the Consensus algorithm are presented for three evaluation items. In order to establish a standardized expression for each evaluation item, the reliability of the node and the success rate of the smart contract were considered as variables in the calculation formula, and the performance of the consensus algorithm of the three groups, PoW/PoS, Paxos/Raft and PBFT, was compared under the same conditions. / analyzed. As a result of the performance evaluation, the network reliability of the three groups was similar, and in the case of the remaining two evaluation items, it was analyzed that the PBFT consensus algorithm was superior to other consensus algorithms. Through the performance evaluation equations and results of this study, it was analyzed that when the PBFT consensus processing process is reflected in the consensus process, the network reliability can be guaranteed and the stability and economic efficiency of the consensus algorithm can be increased.

• Korean Journal of Veterinary Service
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• v.35 no.4
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• pp.289-294
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• 2012

Mycoplasmas are highly fastidious bacteria, difficult to culture and slow growing. Infections with Mycoplasma species can cause a variety of problems in living organisms and in vitro cell cultures. In this study, we investigated the usefulness of a genus-specific consensus PCR analysis method to detect Mycoplasma species. The developed consensus primer pairs MycoF and MycoR were designed specifically to amplify the 16S ribosomal RNA gene (rRNA) of Mycoplasma species by the optimized PCR system. The developed consensus PCR system effectively amplified 215 bp of Mycoplasma genus-specific region of 16S rRNA. In conclusion, we recommend this consensus PCR for monitoring Mycoplasma species in animals, human and cell culture system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.5
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• pp.1218-1224
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• 2008

Located on the upstream of a gene, the promoter region that plays a very important role in the control of gene expression as a signal part has various binding sites for transcription factors. These binding sites are present in various parts of the promoter region and assume an aspect of highly conserved consensus sequence pattern. This paper deals with the introductions of search methods for consensus pattern, including Wataru method, EM algorithm, MEME algorithm, Genetic algorithm and Phylogenetic Footprinting method, and intends to give future prospects of research on this field.

• Journal of Information Processing Systems
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• v.14 no.1
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• pp.101-128
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• 2018

Thanks to its potential in many applications, Blockchain has recently been nominated as one of the technologies exciting intense attention. Blockchain has solved the problem of changing the original low-trust centralized ledger held by a single third-party, to a high-trust decentralized form held by different entities, or in other words, verifying nodes. The key contribution of the work of Blockchain is the consensus algorithm, which decides how agreement is made to append a new block between all nodes in the verifying network. Blockchain algorithms can be categorized into two main groups. The first group is proof-based consensus, which requires the nodes joining the verifying network to show that they are more qualified than the others to do the appending work. The second group is voting-based consensus, which requires nodes in the network to exchange their results of verifying a new block or transaction, before making the final decision. In this paper, we present a review of the Blockchain consensus algorithms that have been researched and that are being applied in some well-known applications at this time.

• Atmosphere
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• v.28 no.3
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• pp.291-303
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• 2018

In this study, a new consensus technique for predicting tropical cyclone (TC) intensity in the western North Pacific was developed. The most important feature of the present consensus model is to select and combine the guidance numerical models with the best performance in the previous years based on various evaluation criteria and averaging methods. Specifically, the performance of the guidance models was evaluated using both the mean absolute error and the correlation coefficient for each forecast lead time, and the number of the numerical models used for the consensus model was not fixed. In averaging multiple models, both simple and weighted methods are used. These approaches are important because that the performance of the available guidance models differs according to forecast lead time and is changing every year. In particular, this study develops both a multi-consensus model (M-CON), which constructs the best consensus models with the lowest error for each forecast lead time, and a single best consensus model (S-CON) having the lowest 72-hour cumulative mean error, through on training process. The evaluation results of the selected consensus models for the training and forecast periods reveal that the M-CON and S-CON outperform the individual best-performance guidance models. In particular, the M-CON showed the best overall performance, having advantages in the early stages of prediction. This study finally suggests that forecaster needs to use the latest evaluation results of the guidance models every year rather than rely on the well-known accuracy of models for a long time to reduce prediction error.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.4
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• pp.179-188
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• 2018

Recently, blockchain technology has been recognized as one of the most important issues for the 4th Industrial Revolution which can be represented by Artificial Intelligence and Internet of Things. Cryptocurrency, named Bitcoin, was the first successful implementation of blockchain, and it triggered the emergence of various cryptocurrencies. In addition, blockchain technology has been applied to various applications such as finance, healthcare, manufacturing, logistics as well as public services. Distributed consensus algorithm is an essential component in blockchain, and it enables all nodes belonging to blockchain network to make an agreement, which means all nodes have the same information. For example, Bitcoin uses a consensus algorithm called Proof-of-Work (PoW) that gives possession of block generation based on the computational volume committed by nodes. However, energy consumption for block generation in PoW has drastically increased due to the growth of computational performance to prove the possession of block. Although many other distributed consensus algorithms including Proof-of-Stake are suggested, they have their own advantages and limitations, and new research works should be proposed to overcome these limitations. For doing this, above all things, we need to establish an evaluation method existing distributed consensus algorithms. Based on this motivation, in this work, we suggest and analyze assessment items by classifying them as efficiency and safety perspectives for investigating existing distributed consensus algorithms. Furthermore, we suggest new assessment criteria and their implementation methods, which can be used for a baseline for improving performance of existing distributed consensus algorithms and designing new consensus algorithm in future.