• Title, Summary, Keyword: Block Chain

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A Study on Implementation of BlockChain Voting System using Hyperledger Fabric (Hyperledger Fabric을 활용한 블록체인 투표시스템 구현에 관한 연구)

  • Hwang, Won-Yong;Kim, Hyo-Kwan
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.13 no.4
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    • pp.298-305
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    • 2020
  • This paper deals with the implementation of electronic voting system using permissioned block chain technology. Cases studies have recently been under way in many industrial areas to review the application of the blockchain based electronic voting system. The existing electronic voting system was easily exposed by hacking because of its centralized characteristics, making it difficult to ensure the reliability and transparency of the voting system itself. In this study, we proposed key considerations and concepts to ensure the reliability and transparency of voters and voting stakeholder by utilizing a hyperledger fabric which is nowadays widely used as a permissioned blockchain.

The Probabilistic Analysis of Fatigue Damage Accumulation Behavior Using Markov Chain Model in CFRP Composites (Markov Chain Model을 이용한 CFRP 복합재료의 피로손상누적거동에 대한 확률적 해석)

  • Kim, Do-Sik;Kim, In-Bai;Kim, Jung-Kyu
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.4
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    • pp.1241-1250
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    • 1996
  • The characteristics of fatigue cumulative damage and fatigue life of 8-harness satin woven CFRP composites with a circular hole under constant amplitude and 2-level block loading are estimated by Stochastic Makov chain model. It is found in this study that the fatigue damage accumulation behavior is very random and the fatigue damage is accumulated as two regions under constant amplitude fatigue loading. In constant amplitude fatigue loading the predicted mean number of cycles to a specified damage state by Markov chain model shows a good agreement with the test result. The predicted distribution of the fatigue cumulative damage by Markov chain model is similar to the test result. The fatigue life predictions under 2-level block loading by Markov chain model revised are good fitted to the test result more than by 2-parameter Weibull distribution function using percent failure rule.

A Study on KSI-based Authentication Management and Communication for Secure Smart Home Environments

  • Ra, Gyeong-Jin;Lee, Im-Yeong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.2
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    • pp.892-905
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    • 2018
  • In smart home environment, certificate based signature technology is being studied by communication with Internet of Things(IoT) device. However, block - chain technology has attracted much attention because of the problems such as single - point error and management overhead of the trust server. Among them, Keyless Signature Infrastructure(KSI) provides integrity by configuring user authentication and global timestamp of distributed server into block chain by using hash-based one-time key. In this paper, we provide confidentiality by applying group key and key management based on multi - solution chain. In addition, we propose a smart home environment that can reduce the storage space by using Extended Merkle Tree and secure and efficient KSI-based authentication and communication with enhanced security strength.

Optimal Maintenance Policy Using Non-Informative Prior Distribution and Marcov Chain Monte Carlo Method (사전확률분포와 Marcov Chain Monte Carlo법을 이용한 최적보전정책 연구)

  • Ha, Jung Lang;Park, Minjae
    • Journal of Applied Reliability
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    • v.17 no.3
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    • pp.188-196
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    • 2017
  • Purpose: The purpose of this research is to determine optimal replacement age using non-informative prior information and Bayesian method. Methods: We propose a novel approach using Bayesian method to determine the optimal replacement age in block replacement policy by defining the prior probability with data on failure time and repair time. The Marcov Chain Monte Carlo simulation is used to investigate the asymptotic distribution of posterior parameters. Results: An optimal replacement age of block replacement policy is determined which minimizes cost and nonoperating time when no information on prior distribution of parameters is given. Conclusion: We find the posterior distribution of parameters when lack of information on prior distribution, so that the optimal replacement age which minimizes the total cost and maximizes the total values is determined.

Past, Present and Future of Blockchain Technology (블록체인 세대별 기술 동향)

  • Park, J.S.;Park, J.Y.;Choi, S.M.;Oh, J.T.;Kim, K.Y.
    • Electronics and Telecommunications Trends
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    • v.33 no.6
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    • pp.139-153
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    • 2018
  • The explosive interest in block chain, which was triggered by Bitcoin in 2009, is leading to substantial investment and the development of block chain technology. There is no dispute among experts that block chain will be the next generation of innovation. However, despite the high expectations for block chains, the related technology still has certain limitations. In addition to improving issues such as a low transaction throughput, inefficient agreement algorithms, and an inflexible governance structure, it is necessary to solve various problems for commercialization and full-scale spreading owing to the trilemma problem among the scalability, security, and decentralization. Under this situation, identification of the technology characteristics according to the generation is helpful for the development of the core technology requirements and commercialization blueprint in establishing an R&D direction. Therefore, in this article, the development of blockchain technology is divided into generations and analyzed in terms of the operational structure, consensus algorithm, governance, scalability, and security.

A Implementation of Blockchain based Manufacturing Supply Chain Tracking System (블록체인 기반 제조 공급망 추적 시스템 구현)

  • Lee, Jae-Ho;Nam, Ho-Ki
    • Journal of the Korea Safety Management and Science
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    • v.19 no.4
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    • pp.183-188
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    • 2017
  • Block Chain is a technology that records and shares distributed ledgers without a central authority, providing a decentralized platform for transparent transactions in the business and enhancing transparency and traceability in all transactions to ensure trust in the transaction. Despite initial doubts about this technology, it is committed to adopting, adapting and improving the technology in a wide range of industries, including finance, government, security, logistics, food, medical, legal, and real estate. This study examines this technology, its applicability and potential benefits to the manufacturing supply chain. A tracking system of manufacturing supply chain to visualize transparency and traceability is implemented, and the conditions for adopting the technology in the manufacturing supply chain and the issues to be addressed are discussed.

Norfloxacin Release from Polymeric Micelle of Poly($\gamma$-benzyl L-glutamate)/Poly(ethylene oxide)/Poly($\gamma$-benzyl L-glutamate)/ Block Copolymer

  • 나재운;정영일;조종수
    • Bulletin of the Korean Chemical Society
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    • v.19 no.9
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    • pp.962-967
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    • 1998
  • Block copolymers consisting of poly(rbenzyl L-glutamate) (PBLG) as the hydrophobic part and poly(ethylene oxide) (PEO) as the hydrophilic part were synthesized and characterized. Polymeric micelles of the block copolymers (abbreviated GEG) were prepared by a dialysis method. The GEG block copolymers were associated in water to form polymeric micelles, and the critical micelle concentration (CMC) values of the block copolymers decreased with increasing PBLG chain length in the block copolymers. Transmission electron microscopy (TEM) observations revealed polymeric micelles of spherical shapes. From dynamic light scattering (DLS) study, sizes of polymeric micelles of GEG-1, GEG-2, and GEG-3 copolymer were 106.5±59.2 nm, 79.4±46.0 nm, and 37.9±13.3 nm, respectively. The drug loading contents of GEG-1, GEG-2 and GEG-3 polymeric micelles were 12.6, 11.9, and 11.0 wt %, respectively. These results indicated that the drugloading contents were dependent on PBLG chain length in the copolymer; the longer the PBLG chain length, the more the drug-loading contents. Release of norfloxacin (NFX) from the nanoparticles was slower in higher loading contents of NFX than in lower loading contents due to the hydrophobic interaction between PBLG core and NFX.

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A NOTE ON FINITE CONDITIONS OF ORTHOMODULAR LATTICES

  • Park, Eun-Soon
    • Communications of the Korean Mathematical Society
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    • v.14 no.1
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    • pp.31-37
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    • 1999
  • We prove the following: every chain-finite OML is path-connected; every finite block of an OML L is path-connected with at least one other block in L; every OML with unifromly finite sites is path-connected.

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Block Chain Application Technology to Improve Reliability of Real Estate Market (부동산 시장의 신뢰성 향상을 위한 블록체인 응용 기술)

  • Oh, Seoyoung;Lee, Changhoon
    • The Journal of Society for e-Business Studies
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    • v.22 no.1
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    • pp.51-64
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    • 2017
  • After Bitcoin was proposed by Satoshi Nakamoto in 2009, studies have been carried out to apply the Block Chain technology in various environment, which was applied as a distributed transaction of Bitcoin. Smart contracts, voting and proof of ownership of digital contents are typical applications of Block Chain. They used the feature that it is impossible to modify or delete once recorded facts. They also applied to prove relevant facts and to provide data integrity. The applied cases are mainly made in an environment where the data should or could be open to the public, and they have been proposed as solutions to solve the problems occurred in relations. This fact has led to the attention that Block Chain can be applied as a good alternative in similar circumstances. In this study, real estate market service was selected to expand the application range of Block Chain. Although there are about 250 applications and web services in total, the satisfaction is not high due to false offerings. Thus we propose a countermeasure against the problem by applying the Block Chain to the real estate market service, and investigate the research direction of the Block Chain in the future market.

Study IoT Asset Management System Based on Block-Chain Framework (블록체인 프레임워크 기반 IoT 자산관리시스템)

  • Kang, Sung Won;Kim, Young Chul
    • Smart Media Journal
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    • v.8 no.2
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    • pp.94-98
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    • 2019
  • In this paper, we developed the tools enabling to manage the IoT systems owned by managers. Since equipment agents consists based on open-source block-chain framework, we can secure the invariance on data and furthermore can locate the resources by searching the AP connected to the equipments. Also the manager can trace the connecting details on equipments from their block-chain accounts. In addition, we work on the possibility of protecting ARP poisoning attacks by removing the credibility on additional ARP requests being generated during the process of network creation.