• Title/Summary/Keyword: Integrity Check

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System Integration Test System Integration Test of Containment Structure of Nuclear Power Plant Using Fiber Optic Sensor (광섬유센서를 이용한 원자력 발전소 격납구조물의)

  • 김기수
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2003.10a
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    • pp.519-526
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    • 2003
  • In this paper, a Fiber Bragg Grating (FRG) sensor system is described and FBGs are well-suited for long term and extremely severe experiments, where traditional strain gauges fail. In the system, a reflect wave-length measurement method which employs a tunable light source to find out the center wave-length of FBG sensor is used. We apply the FBG system to nuclear energy Power Plant for structural integrity test to measure the displacement of the structure under designed pressure and to check the elasticity of the structure by measuring the residual strain. The system works very well and it is expected that it can be used for a real-time strain. temperature and vibration detector of smart structure.

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Study on the Fiber Bragg Grating Sensors for Smart Structures and Their Applications (스마트 구조물용 광섬유 격자센서 및 그 응용)

  • Kim Ki-Soo;Song Young-Chul;Pang Gi-Sung
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2004.04a
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    • pp.115-118
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    • 2004
  • In this paper, a Fiber Bragg Grating (FBG) sensor system for smart structures is described. FBGs are well-suited for long term and extremely severe experiments, where traditional strain gauges fail. In the system, a reflect wave-length measurement method which employs a tunable light source to find out the center wave-length of FBG sensor is used. We applied the FBG system to composite repairing structures and beam column joint of building structure. We also applied the system to nuclear energy power plant for structural integrity test to measure the displacement of the structure under designed pressure and to check the elasticity of the structure by measuring the residual strain. The system works very well and it is expected that it can be used for a real-time strain, temperature and vibration detectors as parts of smart structures.

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Deterministic structural and fracture mechanics analyses of reactor pressure vessel for pressurized thermal shock

  • Jhung, M.J.;Park, Y.W.
    • Structural Engineering and Mechanics
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    • v.8 no.1
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    • pp.103-118
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    • 1999
  • The structural integrity of the reactor pressure vessel under pressurized thermal shock (PTS) is evaluated in this study. For given material properties and transient histories such as temperature and pressure, the stress distribution is found and stress intensity factors are obtained for a wide range of crack sizes. The stress intensity factors are compared with the fracture toughness to check if cracking is expected to occur during the transient. A round robin problem of the PTS during a small break loss of coolant transient has been analyzed as a part of the international comparative assessment study, and the evaluation results are discussed. The maximum allowable nil-ductility transition temperatures are determined for various crack sizes.

Formal Method for Operational Regulations to Railway Signalling System (철도신호시스템 운용규정에 Formal Method의 적용)

  • Kim, He-Eung;Lee, Jong-Woo
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.856-862
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    • 2006
  • In railway signalling system, there are several kinds of signal system such as signals, signs, marker. The signals allows train to go or not, the signs permit to communicate between railway men, and the marks indicate status of railway lines. In KNR, the application of the signal systems are defined in railway operational regulations, operational related regulation, Operation safety critical system manipulation manual, and so on. In this paper, we extracted regulations for signalling system operation from related regulations, reviewed compatibility and contradiction for signalling system operations. We tried to check logical integrity of informal signalling operation regulation using formal method.

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Cryptography in the Cloud: Advances and Challenges

  • Boyd, Colin
    • Journal of information and communication convergence engineering
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    • v.11 no.1
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    • pp.17-23
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    • 2013
  • Cloud computing is a currently developing revolution in information technology that is disturbing the way that individuals and corporate entities operate while enabling new distributed services that have not existed before. At the foundation of cloud computing is the broader concept of converged infrastructure and shared services. Security is often said to be a major concern of users considering migration to cloud computing. This article examines some of these security concerns and surveys recent research efforts in cryptography to provide new technical mechanisms suitable for the new scenarios of cloud computing. We consider techniques such as homomorphic encryption, searchable encryption, proofs of storage, and proofs of location. These techniques allow cloud computing users to benefit from cloud server processing capabilities while keeping their data encrypted; and to check independently the integrity and location of their data. Overall we are interested in how users may be able to maintain and verify their own security without having to rely on the trust of the cloud provider.

Seismic Response Analysis of Freestanding Model of a Spent Fuel Storage Cask (사용후연료 저장용기 자유입상 모델의 지진응답해석)

  • 이재한;서기석;구경회;이홍영;최병일;정성환
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2003.09a
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    • pp.58-65
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    • 2003
  • The seismic response analysis of a freestanding spent fuel storage cask model are performed for an artificial time history acceleration generated by the basis on the US NRC RG1.60 response acceleration spectrum. This paper focuses on the structural stability by seismic loads to check the overturing possibility of storage cask and the slipping displacement on bed. Parametric analyses of a simplified cask model are performed to take into account the variations in seismic load magnitude and cask/bed interface friction. The analyses results show that the storage cask has a large marginal integrity in the response acceleration and slipping distance for both design seismic and beyond design seismic loads.

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A Data Provenance System for Myanmar Rice Cycle Based on Ethereum Blockchain

  • Latt, Cho Nwe Zin;Rahmadika, Sandi;Rhee, Kyung-Hyune
    • Journal of Multimedia Information System
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    • v.8 no.1
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    • pp.35-44
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    • 2021
  • The Myanmar rice cycle's existing system is still relying on a third party to manage every rice data information from several organizations. It is inconvenient to supervise simultaneously due to the unreliability of information provided by organizations. Thus, the rice cycle's original data is challenging to be utterly trusted since irresponsible parties can manipulate the current state of information. Moreover, the applied system does not preserve a proper incentive for the involved parties. In this paper, we leverage the Ethereum blockchain to be adopted to tackle the aforementioned issues. The main objective is to build trust between parties in the Myanmar rice cycle system. Our proposed scheme allows customers to check and trace information about the rice cycle information without worrying about the integrity of the data. Furthermore, the authorized parties are also rewarded by the government through Ethereum smart contract features. Eventually, our scheme achieves traceability in the rice chain system and leads to the complete digitization and automation of the rice cycle information.

CHANGES OF SENSORY AND SOMATOSENSORY EVOKED POTENTIALS FOLLOWING A NEEDLE INJURY ON THE INFERIOR ALVEOLAR NERVE IN RATS (백서 하치조 신경 손상에 따른 감각 유발전위와 체성감각 유발전위의 변화에 관한 연구)

  • Woo, Seung-Chel;Kim, Soo-Nam;Lee, Dong-Keun;Cheun, Sang-Woo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.18 no.4
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    • pp.652-672
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    • 1996
  • Dysfunction of the inferior alveolar nerve may result from trauma, diseases or iatrogenic injury. The development and refinement of an objective method to evaluate this clinical problem is highly desirable and needed, especially concerning for an increasing medico-legal issue. Evoked potential techniques have attracted considerable attention as a means of assessing the function and integrity of nerve pathways. The purpose of this study was to characterize the Sensory Evoked Potentials(SEPs) and Somatosensory Evoked Potentials(SSEPs) elicited by electrical stimulation of mental nerve. SEPs and SSEPs were measured and analyzed statistically before and after needle injury on the inferior alveolar nerve of Sprague-Dawalye rats. Measuring SEPs was more sensitive in evaluation of the recovery of sensory function from inferior alveolar nerve injury then measuring SSEPs but we measured SSEPs in the hope of providing a safe, simple and objective test to check oral and facial sensibility, which is acceptable to the patient. We stimulated mental nerve after needle injury on the inferior alveolar nerve and SEPS on the level of mandibular foramen and SSEPs on the level of cerebral cortex were recorded. Threshold, amplitude, and latency of both of SEPs and SSEPs were analyzed. The results were as follows ; 1. Threshold of SEPs and SSEPs were $184{\pm}14{\mu}A$ and $164{\pm}14{\mu}A$ respectively. 2 SEPs were composed of 2 waves, i.e., N1 N2 in which N1 was conducted by II fibers and N2 was conducted by III fibers. 3. SSEPS were composed of 5 waves, of which N1 and N2 shower statistically significant changes(p<0.01, unpaired t-test). 4. SEPs and SSEPs were observed to be abolished immediately after local anesthesia and recovered 30 minutes later. 5. SEPs were abolished immediately after injury. N1 of SSEPs was abolished immediately and amplitued of N2 was decreased($20.7{\pm}12.2%$) immediately after 23G needle injury, but N3, N4 and N5 did not change significantly. Recovery of waveform delayed 30 minutes in SEPs and 45 minutes in SSEPs. 6. The degree of decrease in amplitude of SEPs and SSEPs, after 30G needle injury was smaller than those with 23G. SEPs recorded on the level of mandibular foramen were though to be reliable and useful in the assessment of the function of the inferior alveolar nerve after injury. Amplitude of SSEPs reflected the function and integrity of nerve and measuring them provided a safe, simple and abjective test to check oral and facial sensibility. These results suggest that measuring SEPs and SSEPs are meaningful methods for objective assessment in the diagnosis of nerve injury. N1 and N2 of SSEPs can be useful parameters for the evaluation of the nerve function following a needle injury.

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Automatic Construction of SHACL Schemas for RDF Knowledge Graphs Generated by Direct Mappings

  • Choi, Ji-Woong
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.10
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    • pp.23-34
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    • 2020
  • In this paper, we proposes a method to automatically construct SHACL schemas for RDF knowledge graphs(KGs) generated by Direct Mapping(DM). DM and SHACL are all W3C recommendations. DM consists of rules to transform the data in an RDB into an RDF graph. SHACL is a language to describe and validate the structure of RDF graphs. The proposed method automatically translates the integrity constraints as well as the structure information in an RDB schema into SHACL. Thus, our SHACL schemas are able to check integrity instead of RDBMSs. This is a consideration to assure database consistency even when RDBs are served as virtual RDF KGs. We tested our results on 24 DM test cases, published by W3C. It was shown that they are effective in describing and validating RDF KGs.

Efficient and Secure Identity-Based Public Auditing for Dynamic Outsourced Data with Proxy

  • Yu, Haiyang;Cai, Yongquan;Kong, Shanshan;Ning, Zhenhu;Xue, Fei;Zhong, Han
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.10
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    • pp.5039-5061
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    • 2017
  • Cloud storage becomes a new trend that more and more users move their data to cloud storage servers (CSSs). To ensure the security of cloud storage, many cloud auditing schemes are proposed to check the integrity of users' cloud data. However, most of them are based on public key infrastructure, which leads to complex certificates management and verification. Besides, most existing auditing schemes are inefficient when user uploads a large amount of data or a third party auditor (TPA) performs auditing for multiple users' data on different CSSs. To overcome these problems, in this paper, we propose an efficient and secure auditing scheme based on identity-based cryptography. To relieve user's computation burden, we introduce a proxy, which is delegated to generate and upload homomorphic verifiable tags for user. We extend our auditing scheme to support auditing for dynamic data operations. We further extend it to support batch auditing in multiple users and multiple CSSs setting, which is practical and efficient in large scale cloud storage system. Extensive security analysis shows that our scheme is provably secure in random oracle model. Performance analysis demonstrates that our scheme is highly efficient, especially reducing the computation cost of proxy and TPA.