• Smart Structures and Systems
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• 제2권3호
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• pp.225-235
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• 2006

With the discovery in plants of the proteinaceous forisome crystalloid (Knoblauch, et al. 2003), a novel, non-living, ATP-independent biological material became available to the designer of smart materials for advanced actuating and sensing. The in vitro studies of Knoblauch, et al. show that forisomes (2-4 micron wide and 10-40 micron long) can be repeatedly stimulated to contract and expand anisotropically by shifting either the ambient pH or the ambient calcium ion concentration. Because of their unique abilities to develop and reverse strains greater than 20% in time periods less than one second, forisomes have the potential to outperform current smart materials as advanced, biomimetic, multi-functional, smart sensors or actuators. Probing forisome material properties is an immediate need to lay the foundation for synthesizing forisomebased smart materials for health monitoring of structural integrity in civil infrastructure and for aerospace hardware. Microfluidics is a growing, vibrant technology with increasingly diverse applications. Here, we use microfluidics to study the surface interaction between forisome and substrate and the conformational dynamics of forisomes within a confined geometry to lay the foundation for forisome-based smart materials synthesis in controlled and repeatable environment.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2012년 춘계학술대회
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• pp.43-59
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• 2012

As contemporary building construction type is getting higher and deeper,construction equipment usage is getting more, and related fatal accidents are on an increasing trend. In these days, due to the deteriorating construction business circumstance, job finding problem of equipment operator, and dumping contract, equipment lease suppliers are putin jeopardy. In high-rise building construction, especially tower crane, mobile elevated work platform and other High place operation cars among construction equipment cause many critical accidents because of drop supply of construction biding bringing out dumping contract could cause unsafe and poor construction management. Because of this, a method was drawn which could grasp the present state of construction equipment management and manage safety of the equipment more easily for accident prevention by choosing 2 kinds of Construction equipment which cause safety accident frequently among the equipment mainly used in construction site. This study suggested a method about construction equipment safety management using "smart phone" base which could be used in safety management for construction equipment by whomever in construction site. After attachment of QR code included safety checklist, It became possible that site managers could check more efficiently by scanning with their smart phone when they inspect equipment. Moreover, by the construction interested who didn't know what and how they have to inspect could point out unsafe condition in the early stage of equipment entering or take unsafe one out of the site by using new smart phone safety checking system is installed, it became possible that critical accident caused by construction equipment was prevented in advance.

• 스마트미디어저널
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• 제10권3호
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• pp.48-53
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• 2021

인증 프로세스는 사용자가 합법적인지 확인하는 데 사용되어야 하는 주요 단계이며, 사용자가 합법적인 사용자인지 확인하고 해당 사용자에게만 액세스 권한을 부여하는 데 사용되어야 한다. 최근에는 로그인 프로세스에 보안 계층을 추가하여 인증에 하나의 요소만 사용하는 취약점을 해결하기 위해 대부분의 애플리케이션에서는 이중인증과 OTP체계를 사용하고 있지만, 이 방법도 허가 없이 사용자 계정에 액세스할 수 있는 방법이 알려져 보안에 취약하다. 본 논문에서는 최소한의 개인정보만을 노출 조건으로 사용자를 인증하는 블록체인의 Smart Contract 기반으로 영지식(ZKP:Zero Knowledge Proofs)개인정보 인증 기법을 제안한다. 이는 블록체인 기술을 기반으로 인증 프로세스에 많은 보안 기술을 제공하고, 개인정보 인증을 기존의 인증방식보다 안전하게 수행할 수 있다는 장점이 있다.

• 한국인터넷방송통신학회논문지
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• 제18권5호
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• pp.259-265
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• 2018

상품의 공급 방식이 다양해지고 복잡해지면서 기존의 공급망 시스템 안의 유통과정에서 원산지 둔갑, 상품 추적 불가 등 여러 가지 문제점들이 발생하기 시작하였다. 이러한 이슈들을 다루기 위하여, SW 업계와 학계는 다양한 블록체인 기반의 연구를 시도하고 있다. 그러나, 제안한 블록체인 기술에 대한 광범위한 조사 연구가 진행되어 있지 않아, 해당 기술에 대한 장단점을 이해하기 어렵다. 본 연구에서 우리는 목표, 사용된 핵심 블록체인 기술 및 IoT 기술과 같은 기준으로 SW 업계와 학계에서 제안된 다양한 연구를 집중적으로 연구 조사 하였다. 본 논문에서는 선정된 논문들과 실제 적용 산업 사례들에 대해 간략하게 소개하고 선정 기준과 사용된 기술을 smart contract 와 IoT기술을 기준으로 비교하여 서술하였다.

• 한국IT서비스학회지
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• 제16권4호
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• pp.213-222
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• 2017

The advancement of ICT is changing every field of life. It becomes possible with the penetration of personalized devices, that is, smartphone. The boom of IoT will come when there exist diversified and personalized services. In general, we might admit that it is needed that the more privatized services than the overall serviced. Jeju Island is the only one special self-governing province in Republic of Korea and deserves to be proud of the unique culture from its long historical background. One of the very regional culture which performs by women divers, Haenyeo activity or culture, was registered as Intangible Cultural Heritage. When authors were researched Jeju Haenyeo as a worthy reserving service, we recognized that it has never considered to use any point of ICT/IoT yet. Because IoT holds the high potentiality to create any service scenario between interesting groups. We will design a few services for Haenyeo which covers their job territory or daily life, adopts up-to-date technology or method such as sensored network, smart contract and App/Web. In this paper, we intent to show the simplicity and easiness of the application of IoT not to much inconspicuous target. So, we suggest a specialized IoT service for the reservation and promotion of Haenyeo Culture. This service would be composed of sensors, IoT network and App/Web at home and office. This service can be used among interesting groups : Haenyeo, policy maker, manufacturer, service provider and culture consumer.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권8호
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• pp.2849-2864
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• 2021

The emerging of cloud data sharing can create great values, especially in multi-cloud environments. However, "data island" between different cloud service providers (CSPs) has drawn trust problem in data sharing, causing contradictions with the increasing sharing need of cloud data users. And how to ensure the data value for both data owner and data user before sharing, is another challenge limiting massive data sharing in the multi-cloud environments. To solve the problems above, we propose a Uniform Encoding and Parsing Framework (UEPF) with blockchain to support trustworthy and valuable data sharing. We design namespace-based unique identifier pair to support data description corresponding with data in multi-cloud, and build a blockchain-based data encoding protocol to manage the metadata with identifier pair in the blockchain ledger. To share data in multi-cloud, we build a data parsing protocol with smart contract to query and get the sharing cloud data efficiently. We also build identifier updating protocol to satisfy the dynamicity of data, and data check protocol to ensure the validity of data. Theoretical analysis and experiment results show that UEPF is pretty efficient.

• ETRI Journal
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• 제43권2호
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• pp.357-370
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• 2021

The evolution of blockchain-based systems has enabled researchers to develop nextgeneration e-voting systems. However, the classical consensus method of blockchain, that is, Proof-of-Work, as implemented in Bitcoin, has a significant impact on energy consumption and compromises the scalability, efficiency, and latency of the system. In this paper, we propose a hybrid consensus model (PSC-Bchain) composed of Proof of Credibility and Proof of Stake that work mutually to address the aforementioned problems to secure e-voting systems. Smart contracts are used to provide a trustworthy public bulletin board and a secure computing environment to ensure the accuracy of the ballot outcome. We combine a sharding mechanism with the PSC-Bchain hybrid approach to emphasize security, thus enhancing the scalability and performance of the blockchain-based e-voting system. Furthermore, we compare and discuss the execution of attacks on the classical blockchain and our proposed hybrid blockchain, and analyze the security. Our experiments yielded new observations on the overall security, performance, and scalability of blockchain-based e-voting systems.

• Journal of Multimedia Information System
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• 제6권3호
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• pp.139-146
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• 2019

This paper, wireless internet such as Wi-Fi has a vulnerability to security. Blockchain also means a 'Ledger' in which transaction information that occurs on a public or private network is encrypted and shared among the network participants. Blockchain maintains information integrity by making it impossible for a particular node to tamper with information arbitrarily, a feature that would result in changes in the overall blockchain hash value if any one transaction information that constitutes a block was changed. The complete sharing of information through a peer-to-peer network will also cripple hacking attempts from outside, targeting specialized nodes, and prepare for the "single point of failure" risk of the entire system being shut down. Due to the value of these Blockchain, various types of Blockchain are emerging, and related technology development efforts are also actively underway. Various business models such as public block chains such as Bitcoin, as well as private block chains that allow only certain authorized nodes to participate, or consortium block chains operated by a select few licensed groups, are being utilized. In terms of technological evolution, Blockchain also shows the potential to grow beyond cryptocurrency into an online platform that allows all kinds of transactions with the advent of 'Smart Contract'. By using Blockchain technology, the company makes suggestions to overcome the vulnerability of wireless Internet.

• 디지털융복합연구
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• 제17권10호
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• pp.13-21
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• 2019

제한된 네트워크 자원과 불균등한 전파 자원 분배로 인해 전파자원 부족 문제와 서비스 품질 열화가 발생하고 있다. 또한, 기존 중앙집중식 전파 공유 방식은 전파 공유 활성화를 위한 근본적인 해결책이 되지 못하고 있으며 비용, 편의성, 보안성 관점에서 비효율적이다. 본 논문에서는 전파자원을 분배하고 공유할 수 있는 저비용, 고신뢰, 고효율 플랫폼으로서 블록체인 기반의 스펙트럼 쉐어링 플랫폼을 제안하고 이를 실현하기 위한 법적 쟁점을 분석하였다. 스펙트럼 쉐어링 플랫폼에서는 와이파이 AP 전파 정보와 LTE 모바일 핫스팟 전파 정보를 블록체인에 등록하고, 전파 공유자와 전파 사용자가 스마트 컨트랙트 통해 개인 간 (P2P) 전파 공유 계약을 빠르고 효율적으로 체결한다. 전파 공유에 대한 대가와 품질 관리에 대한 보상인 암호화폐는 선순환적인 전파 공유 오픈 플랫폼 생태계를 활성화할 것이며, 스펙트럼 쉐어링 플랫폼을 통해 편리하고 효율적인 공공 무선 인프라를 제공할 수 있다.

• 한국정보전자통신기술학회논문지
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• 제14권3호
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• pp.201-207
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• 2021

머신러닝의 한 종류인 딥러닝은 각 학습 과정을 진행할 때, 가중치를 변경하면서 학습을 수행한다. 딥러닝을 수행할때 대표적으로 사용되는 Tensor Flow나 Keras의 경우 학습이 종료된 결과를 그래프 형태로 제공한다. 이에 과다학습으로 인한 퇴화 현상 또는 가중치의 잘못된 설정으로 인해 학습 결과에 오류가 발생하는 경우, 해당 학습 결과를 폐기해야한다. 이에 기존 기술은 학습 결과를 롤백하는 기능을 제공하고 있지만, 롤백 기능은 최대 5회 이내의 결과로 제한된다. 또한, 딥러닝의 모든 과정을 기록하고 있는 것이 아니기 때문에 값을 추적하기 어렵다. 이를 해결하기 위해 MLOps의 개념을 적용한 기술이 존재하지만. 해당 기술에서는 이전 시점으로 롤백하는 기능을 제공하지 않는다. 본 논문에서는 기존 기술의 문제점을 해결하기 위해 학습 과정의 중간 값을 블록체인으로 관리하여 학습 중간 과정을 기록하고, 오류가 발생할 경우 롤백할 수 있는 시스템을 구성한다. 블록체인의 기능 수행을 위해서 딥러닝 과정 및 학습 결과 롤백은 Smart Contract를 작성하여 동작하도록 설계하였다. 성능평가는 기존의 딥러닝 방식의 롤백 기능을 평가하였을 때, 제안방식은 100%의 복구율을 가지는 것에 비교하여 기존 기법에서는 6회 이후에 복구율이 감소되어 50회일 때 10%까지 감소하는 것을 확인하였다. 또한, 이더리움 블록체인의 Smart Contract를 사용할 때, 블록 1회 생성 시 157만원의 금액이 지속적으로 소모되는 것을 확인하였다.