• Title/Summary/Keyword: Block Chain

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Blockchain-based authentication for IoT

  • Alaa Alsubhi;Jawaher Alhrthi;Wajdi Alhakami
    • International Journal of Computer Science & Network Security
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    • v.24 no.5
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    • pp.198-204
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    • 2024
  • Correspondence security between IoT devices is a significant concern, and the blockchain makes the latest difference by reducing this matter. In the blockchain idea, the larger part or even all organization hubs check the legitimacy and precision of traded information before tolerating and recording them, regardless of whether this information is identified with monetary exchanges or estimations of a sensor or a confirmation message. In assessing the legitimacy of a traded information, hubs should agree to play out an uncommon activity. The chance to enter and record exchanges and problematic cooperation with the framework is fundamentally decreased. To share and access the executives of IoT devices data with disseminated demeanour, another confirmation convention dependent on block-chain is proposed, and it is guaranteed that this convention fulfils client protection saving and security. This paper highlights the recent approaches conducted by other researchers to secure the Internet of Things environments using blockchain. These approaches are studied and compared with each other to present their features and disadvantages.

Comparison Between T2 and T2.3 Thoracic Sympathetic Block in Palmar Hyperhidrosis (수장부 다한증에서 제 2번 및 제 2,3번 흉부 교감신경절 차단술의 비교)

  • 성숙환;조광리;김영태;김주현
    • Journal of Chest Surgery
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    • v.31 no.10
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    • pp.999-1003
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    • 1998
  • Background: Thoracoscopic sympathetic block in palmar hyperhidrosis has merits in its immediate responsiveness and recovery. In palmar hyperhidrosis, the level of sympathetic chain to be blocked has been somewhat obscure. Materials and methods: To compare the results of T2 with T2,3 sympathetic block, we retrospectively studied 192 patients (T2 group: 84, T23 group: 108) operated on at SNUH with palmar hyperhidrosis between April 1994 and July 1997. We reviewed medical records and recently interviewed the patients by telephone call. Sex and age distribution between two groups showed no significant differences. We performed sympathectomy at the early phase of the syudy until April 1997, and after then, we adopted sympathicotomy rather than sympathectomy. Results: All patients showed symptomatic improvement after the operation. Mean operation times of T2, T23 groups were 61.3$\pm$22.5min, 82.7$\pm$24.8min, respectively(p<0.01). Early postoperative complications, such as Horner's syndrome or chest tube insertion, were not different in two groups. There were no statistical differences of late complications such as compensatory truncal hyperhidrosis, gustatory sweating, and phantom sweating. No patient experienced recurrence of palmar hyperhidrosis during the study period. The only difference was the extent of compensatory truncal hyperhidrosis. The compensatory sweating occurred from axilla to suprapatella in T2 group whereas its extent was from nipple to suprapatella in T23 group. Conclusions: We concluded that T2 thoracic sympathetic block is mandatory for the treatment of primary palmar hyperhidrosis.

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A Study on Lightweight Block Cryptographic Algorithm Applicable to IoT Environment (IoT 환경에 적용 가능한 경량화 블록 암호알고리즘에 관한 연구)

  • Lee, Seon-Keun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.3
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    • pp.1-7
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    • 2018
  • The IoT environment provides an infinite variety of services using many different devices and networks. The development of the IoT environment is directly proportional to the level of security that can be provided. In some ways, lightweight cryptography is suitable for IoT environments, because it provides security, higher throughput, low power consumption and compactness. However, it has the limitation that it must form a new cryptosystem and be used within a limited resource range. Therefore, it is not the best solution for the IoT environment that requires diversification. Therefore, in order to overcome these disadvantages, this paper proposes a method suitable for the IoT environment, while using the existing block cipher algorithm, viz. the lightweight cipher algorithm, and keeping the existing system (viz. the sensing part and the server) almost unchanged. The proposed BCL architecture can perform encryption for various sensor devices in existing wire/wireless USNs (using) lightweight encryption. The proposed BCL architecture includes a pre/post-processing part in the existing block cipher algorithm, which allows various scattered devices to operate in a daisy chain network environment. This characteristic is optimal for the information security of distributed sensor systems and does not affect the neighboring network environment, even if hacking and cracking occur. Therefore, the BCL architecture proposed in the IoT environment can provide an optimal solution for the diversified IoT environment, because the existing block cryptographic algorithm, viz. the lightweight cryptographic algorithm, can be used.

Solvent-Polymer Interactions for Stable Non-Aqueous Graphene Dispersions in the Presence of PVK-b-PVP Block Copolymer (PVK-b-PVP 블록 공중합체의 존재 하에서 안정한 비 수계 그래핀 분산액을 위한 용매-고분자 상호작용에 관한 연구)

  • Park, Kyung Tae;Perumal, Suguna;Lee, Hyang Moo;Kim, Young Hyun;Cheong, In Woo
    • Journal of Adhesion and Interface
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    • v.18 no.3
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    • pp.109-117
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    • 2017
  • Poly(N-vinyl carbazole) (PVK) homopolymer, poly(4-vinylpyridine) (PVP) homopolymer, and PVK-b-PVP block copolymer were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization and the polymers were used to prepare non-aqueous graphene dispersions with four different solvents, ethanol, N-methyl-2-pyrrolidone (NMP), dichloromethane (DCM), and tetrahydrofuran (THF). $^1H-$ and $^{13}C-NMR$ spectroscopy, size exclusion chromatography (SEC), and differential scanning calorimetry (DSC) were carried out to confirm the chemical structure of the polymers. Stability of graphene dispersions was measured by on-line turbidity measurement. Time-dependent Turbiscan Stability Index (TSI) values were interpreted in terms of surface tension (${\sigma}$) and solubility parameter (${\delta}$) among solvents, polymers, and graphene. It was confirmed that the solubilities of polymer and surface tension between solvent and graphene affected the dispersion stability of graphene. PVK-b-PVP block copolymer could effectively maintain the low TSI values of graphene dispersions in ethanol and THF, which have been known as poor solvents for graphene dispersions. It can also be noted that DCM shows good dispersion stability comparable to NMP, which has been known as the best solvent for graphene dispersion.

The Influence of E-beam Irradiation on POLY(ETHER-BLOCK-AMIDE) (PEBA, Pebax) (전자 빔 조사후 PEBA (Poly Ether Block Amide)의 구조 및 기계적 특성 변화)

  • Shin, Sukyoung;Cho, SangGyu
    • Progress in Medical Physics
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    • v.25 no.4
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    • pp.205-209
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    • 2014
  • Medical polymers require sterilization and must be able to maintain material properties for a specified shelf life. Sterilization can be achieved by using gamma or e-beam exposure. In this study, accelerated aging tests of poly(ether-block-amide) (PEBA) copolymer samples is presented. PEBA copolymer samples with different polyether content that result in Shore hardness of 35D to 72D, were sterilized using e-beam radiation followed by accelerated aging at $55^{\circ}C$. E-beam sterilization effect on molecular weight and mechanical property has performed and analyzed. The average molecular weight significantly reduced as a result of ageing. The enlarged proportion of low molecular weight chains in the aged samples is consistent with the generation of degradation products produced by oxidative chain scission. Also E-beam materials have shown decreased tensile strength and elongation. Overall, this study demonstrated that the medical grade PEBA was significantly affected by radiation exposure over aging time, particularly at high irradiation doses. For medical use in case of radiation sterilization required, it is recommended to avoid Pebax material. If Pebax material must be in use for medical device, recommend to use alternate sterilization method such as Ethylene Oxide sterilization.

A Static and Dynamic Design Technique of Smart Contract based on Block Chain (블록체인 기반의 스마트 컨트랙트 정적/동적 설계 기법)

  • Kim, Chul-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.6
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    • pp.110-119
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    • 2018
  • Blockchain technology has been highly evaluated for its contracts (contracts for sale, real estate contracts) because of its excellent security, including integrity and non-repudiation. In a blockchain, these contract services can be developed using a technology called a smart contract, and several blockchain platforms provide a programming language for developing smart contracts. Bitcoin and Ethereum, typical blockchain platforms, provide the Bitcoin Scripts and Solidity languages. Using these programming languages, we can develop the smart contract, a digital contract that can be processed dynamically. Smart contracts are being developed in a variety of areas, but studies of designs based on a blockchain are insufficient. In this paper, we propose a meta-model and a static/dynamic design method based on Unified Modeling Language (UML) for smart contracts based on Ethereum. We propose a method for static design attributes and functions of smart contracts, and propose a technique for designing structures among contracts. Dynamic design proposes a technique for designing deployment, function calls, and synchronization among smart contracts, accounts, and blocks within a blockchain. Experiments verify the validity of the design method by applying the static/dynamic design method through real estate contracts.

A Study to Accept Block Chain System on Medical Industry (의료산업 블록체인 도입을 위한 연구)

  • Park, Jung-Hong
    • The Journal of the Korea Contents Association
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    • v.18 no.6
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    • pp.155-168
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    • 2018
  • The purpose of this study was to investigate characteristics of Blockchain to introduce Blockchain technology to the medical industry. Thus, the 5 factors such as Security, Availability, Reliability, Diversity and Economic feasibility were used as the characteristics of Blockchain, which are independent variable, based on precedent studies. Also, Technology Acceptance Model(TAM) that are widely used in the research on Acceptance Intention in order to introduce new technology accept was utilized for intervening variable and dependent variable. For the purpose of this study, the health professionals and ordinary people were classified into health care providers and medical service consumers respectively to conduct survey and comparative analysis. The researching findings discovered that Hypothesis1-1(Security-Perceived Easiness-Acceptance Intention), Hypothesis2-1(Security-Perceived Usefulness-Acceptance Intention) and Hypothesis 3-1(Security-Perceived Easiness-Perceived Usefulness-Acceptance Intention) were rejected in all participants including health professionals and ordinary people. Additionally, all characteristics of Blockchain such as Availability, Reliability, Diversity and Economic feasibility were rejected in Hypothesis3-2 and Hypothesis 3-5 that pass through Easiness and Usefulness to Acceptance Intention, in case of the medical service consumers. Thus, this study discovered and confirmed that there's difference between the health care providers and medical service in the characteristics of Blockchain, as they pass through Perceived Easiness and Perceived Usefulness to Acceptance Intention. The significance of this study can be found, as it suggested activation plan through empirical analysis, which was hardly ever used in the study on Blockchain activation.

Study on the Fourth Industrial Revolution and Clinical Laboratory Science Techniques (4차 산업혁명과 임상검사과학기술에 관한 연구)

  • Sung, Hyun Ho;Choi, Kwang-Mo;Jung, You Hyun;Cho, Eun Kyung
    • Korean Journal of Clinical Laboratory Science
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    • v.51 no.3
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    • pp.386-395
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    • 2019
  • The aim of this study was to introduce clinical laboratory science techniques with the core technology of the 4th Industrial Revolution. Among the core technologies of the 4th Industrial Revolution, AI, IOT, block-chain, robotics, and nanotechnology were analyzed and linked by themes. The scope of the job of clinical laboratory technologists (also known as medical laboratory technologists and medical technologists) is laboratory medicine testing, pathology testing, and clinical physiology testing. Through a number of previous papers, 73 linkages in the laboratory medicine area, 27 linkages in the pathology area, and 47 linkages in the clinical physiology area were examined. In the 4th industrial revolution and clinical laboratory science techniques, AI (4), IOT (3), block-chain (4), robotics (3) and nanotechnology (15) sectors were surveyed. The limitation of this study was the limitation in collecting and analyzing all the data and non-clinical areas were not analyzed. In addition, there was no validity test and no similar study. In conclusion, the core technologies of the 4th industrial revolution and clinical laboratory science techniques are closely related. Therefore, further research on the future and social benefits of clinical laboratory science techniques is needed.

A System Recovery using Hyper-Ledger Fabric BlockChain (하이퍼레저 패브릭 블록체인을 활용한 시스템 복구 기법)

  • Bae, Su-Hwan;Cho, Sun-Ok;Shin, Yong-Tae
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.12 no.2
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    • pp.155-161
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    • 2019
  • Currently, numerous companies and institutes provide services using the Internet, and establish and operate Information Systems to manage them efficiently and reliably. The Information System implies the possibility of losing the ability to provide normal services due to a disaster or disability. It is preparing for this by utilizing a disaster recovery system. However, existing disaster recovery systems cannot perform normal recovery if files for system recovery are corrupted. In this paper, we proposed a system that can verify the integrity of the system recovery file and proceed with recovery by utilizing hyper-ledger fabric blockchain. The PBFT consensus algorithm is used to generate the blocks and is performed by the leader node of the blockchain network. In the event of failure, verify the integrity of the recovery file by comparing the hash value of the recovery file with the hash value in the blockchain and proceed with recovery. For the evaluation of proposed techniques, a comparative analysis was conducted based on four items: existing system recovery techniques and data consistency, able to data retention, recovery file integrity, and using the proposed technique, the amount of traffic generated was analyzed to determine whether it was actually applicable.

A Study on the Technological Priorities of Manufacturing and Service Companies for Response to the 4th Industrial Revolution and Transformation into a Smart Company (4차 산업혁명 대응과 스마트 기업으로의 변화를 위한 제조 및 서비스 기업의 기술적용 우선순위에 대한 연구)

  • Park, Chan-Kwon;Seo, Yeong-Bok
    • Journal of Convergence for Information Technology
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    • v.11 no.4
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    • pp.83-101
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    • 2021
  • This study is to investigate, using AHP, what technologies should be applied first to Korean SMEs in order to respond to the 4th industrial revolution and change to a smart enterprise. To this end, technologies related to the 4th industrial revolution and smart factory are synthesized, and the classification criteria of Dae-Hoon Kim et al. (2019) are applied, but additional opinions of experts are collected and related technologies are converted to artificial intelligence (AI), Big Data, and Cloud Computing. As a base technology, mobile, Internet of Things (IoT), block chain as hyper-connected technology, unmanned transportation (autonomous driving), robot, 3D printing, drone as a convergence technology, smart manufacturing and logistics, smart healthcare, smart transportation and smart finance were classified as smart industrial technologies. As a result of confirming the priorities for technical use by AHP analysis and calculating the total weight, manufacturing companies have a high ranking in mobile, artificial intelligence (AI), big data, and robots, while service companies are in big data and robots, artificial intelligence (AI), and smart healthcare are ranked high, and in all companies, it is in the order of big data, artificial intelligence (AI), robot, and mobile. Through this study, it was clearly identified which technologies should be applied first in order to respond to the 4th industrial revolution and change to a smart company.