• Title/Summary/Keyword: Integrity Check

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Evaluation of the Structural Stability of Platform Screen Door(PSD) (승강장 스크린 도어(PSD)시스템의 구조 안정성 평가)

  • Lee, Jae-Youl;Ryu, Bong-Jo;Jeon, Jae-Sun;Kim, Dong-Hyun;Lee, Eun-Kyu;Shin, Kwang-Bok
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.1190-1197
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    • 2006
  • We have evaluated the structural stability of a platform screen door due to train wind pressure. The platform screen door was installed at the ground and underground station and had 65 meters in length. Also, the platform screen door was a safety device because it was placed between the train and the platform. The finite element analysis was used to calculate the stresses and deflections of platform screen door caused by wind pressure using ANSYS 10.0. Quasi-static analysis was introduced to save calculating time and check quickly structural performances when compared to those of transient analysis. The results show that structural stability of the platform screen door under train wind pressure is proven and quasi-static analysis can quickly check the structural integrity of platform screen door.

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Deterministic Fracture Mechanics Analysis of Pressurized Thermal Shock

  • M. J. Jhung;Park, Y. W.
    • Nuclear Engineering and Technology
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    • v.30 no.5
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    • pp.470-484
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    • 1998
  • An analysis program for the evaluation of pressure vessel integrity under pressurized thermal shock (PTS) is developed. For given material properties and transient history such as temperature and pressure, the stress distribution is calculated and then 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. Using this program a round robin problem of PTS during a small break loss of coolant transient has been analyzed as a part of the international comparative assessment study. The allowable maximum reference nil-ductility transition temperatures are determined for various crack sizes.

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광섬유 센서를 이용한 원자력 발전소 격납구조물의 가동전 가압 팽창을 통한 구조건전성 시험

  • 김기수
    • Composites Research
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    • v.16 no.6
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    • pp.56-61
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    • 2003
  • In this Paper, a fiber Bragg grating(FBG) 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.

The Performance Evaluation for the Rail Road Train Spring (철도차량용 스프링의 On-Line 성능 평가 방법 연구)

  • 백수곤;박종범;김상봉;하승우;서승후
    • Proceedings of the KSR Conference
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    • 2001.05a
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    • pp.178-185
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    • 2001
  • So many springs in the rail road trains have been degeaded by the long time operation. Specially vibrations makes worse the condition of the springs. The performance evaluation technique for the rail road spring was developed. Using integrated handy tools using hydraulic systems, LVDT, and related software, On-line evaluation is possible to check the system integrity.

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Kernel Integrity Check and Restoration through Kernel Image Comparison (커널이미지 비교에 의한 커널 무결성 검사 및 복구)

  • 김일용;김기창
    • Proceedings of the Korean Information Science Society Conference
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    • 2002.10c
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    • pp.562-564
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    • 2002
  • 최근 커널의 특정부분을 사용자 임의로 수정하여 시스템을 공격하는 여러 가지 기법들, 즉 커널 백도어가 늘어나고 있다. 이 커널 백도어의 문제점은 커널 자체를 수정하기 때문에 탐지 및 복구가 힘들다는 것이다. 이에 대응하여 커널 백도어를 탐지하는 대부분의 방법이 특정 주소를 검사하여 이루어지는데 이는 확실한 탐지에는 한계가 있다. 설사 탐지는 가능하다 하더라도 복구는 거의 불가능한 것이 현실이다. 이에 본 논문에서는 커널이 기동될 때 사용되는 순수한 부트 이미지와 커널에서 실행중인 이미지를 비교하여 커널의 무결성을 검사, 복구하는 시스템을 제안한다.

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(Infirmation Technology- Security techniques- Data integrity mechanism using a cryptographic check function employing a block ciipher algorithm) (IOS/IEC JTC1/SC27의 국제표준소개 (2) : 정보기술-보안기술-블럭 암호화 알고리즘을 사용하여 만든 암호학적 검산 함수를 이용한 데이타 무결성 기법)

  • 이필중
    • Review of KIISC
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    • v.3 no.3
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    • pp.31-39
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    • 1993
  • IOS/IEC JTC1/SC27의 국제표준소개의 첫번째 편으로 DIS 9797을 소개한다. 이것은 1989년에 1차로 국제표준이 되었다가 결함이 발견되어 다시 작업이 시작되어 1992년 10월 SC27정기총회에서 CD(Committee Draft)에서 수정후 DIS(Draft Internationa Standard) 수준으로 올리기로 하여 1993년 3월 DIS로서 표결에 부쳐진 문서이다. 이해를 돕기 위하여 국문뒤에 원문을 덧붙였다. 번역이 적절하지 않거나 더 좋은 표현이 있으면 역자에게 알려주면 참고하여 추후의 수정본에 반영하겠다.

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Effects of Group Art Therapy to Improve Self-esteem and Enhance Self-integrity of Rural Elderly Women (농촌여성노인의 자아존중감 향상 및 자아통합감 증진을 위한 집단미술치료 프로그램 효과)

  • Kim, Jong Hee
    • 한국노년학
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    • v.34 no.2
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    • pp.259-275
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    • 2014
  • The purpose of this study is to check if group art therapy is effective in improving self esteem and self integrity of rural elderly women. Study subjects are forty seven rural elderly women in A-city who have participated in producing specialized products in their rural area. They are divided into experimental group (EG, n=25) who wish to participate in the group art therapy program, a part of the A-city sponsored program named 'Making the Rural Elderly Happy', to improve and enhance the elderly's self esteem and self integrity, and control group (CG, n=22) with no wish to participate. However, only forty four elderly women are selected as the final study subjects for data analysis, due to those who either missed the program session more than once or died of old age during the program period. The group art therapy program was given from March 16 to May 18 of 2010, every Tuesday between 1pm through 3pm for a total of 12 sessions, with the help of two college student assistants in the region and one staff member for the city program. SPSS WIN version 12.0 is adopted to evaluate and analyze the effects of the therapy program, independent t-test for equivalence check of pretests, and frequency check for general characteristics of each group. The study results are obtained by the mean and standard deviation to grasp the changes between pretest and post-test on both groups, together with ANCOVA to evaluate effects of the therapy program with the pre-test as covariant. The results are as follows. First, self esteem of EG is significantly improved than that of CG after intervention of group art therapy. Second, self integrity is significantly higher in EG than CG after the group art therapy intervention. Therefore, it can be claimed that group art therapy is effective in improving and enhancing self esteem and self integrity of the rural elderly women.

Privacy-Preserving Self-Certified Public Auditing for Secure Cloud Storage (안전한 클라우드 스토리지를 위한 프라이버시 보장 자체 인증 공공 감사)

  • Baek, Mokryeon;Kim, Dongmin;Jeong, Ik Rae
    • Journal of KIISE
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    • v.43 no.4
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    • pp.497-508
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    • 2016
  • With a cloud storage service, data owners can easily access their outsourced data in cloud storage on different devices and at different locations, and can share their data with others. However, as the users no longer physically have possession of their outsourced data and the cloud still facing the existence of internal/external threats, the task of checking the data integrity is formidable. Over recent years, numerous schemes have been proposed to ensure data integrity in an untrusted cloud. However, the existing public auditing schemes use a third-party auditor(TPA) to execute high computation to check data integrity and may still face many security threats. In this paper, we first demonstrate that the scheme proposed by Zhang et al. is not secure against our two threat models, and then we propose a self-certified public auditing scheme to eliminate the security threats and guarantee a constant communication cost. Moreover, we prove the securities of our public auditing scheme under three security models.

A Study on Integrity Verification and Tamper Detection of Digital Image (디지털 영상의 무결성 검증과 변형 검출에 관한 연구)

  • Woo, Chan-Il;Goo, Eun-Hee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.10
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    • pp.203-208
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    • 2019
  • Digital watermarking was developed to protect copyright by discouraging the illegal copying of digital content. On the other hand, recently, watermarking has also been used to verify the integrity of digital content, such as medical images, and detect illegal manipulation or distortion locations. Watermarking should be tenacious so as to protect copyright from illegal copying and should remain firm to the content through a range of attacks, such as distortion or filtering. At the same time, however, it should be removed easily even in a slight transformation of the material to verify the integrity. Therefore, this paper proposes a watermarking technique that easily checks and verifies the deformation or manipulation of digital images. In the proposed method, the entire image was examined in $16{\times}16$ blocks to check for deformation of the image. When deformation was detected, further inspection proceeded in $4{\times}4$ blocks and the location where deformation occurred was identified.

Verification Algorithm for the Duplicate Verification Data with Multiple Verifiers and Multiple Verification Challenges

  • Xu, Guangwei;Lai, Miaolin;Feng, Xiangyang;Huang, Qiubo;Luo, Xin;Li, Li;Li, Shan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.2
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    • pp.558-579
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    • 2021
  • The cloud storage provides flexible data storage services for data owners to remotely outsource their data, and reduces data storage operations and management costs for data owners. These outsourced data bring data security concerns to the data owner due to malicious deletion or corruption by the cloud service provider. Data integrity verification is an important way to check outsourced data integrity. However, the existing data verification schemes only consider the case that a verifier launches multiple data verification challenges, and neglect the verification overhead of multiple data verification challenges launched by multiple verifiers at a similar time. In this case, the duplicate data in multiple challenges are verified repeatedly so that verification resources are consumed in vain. We propose a duplicate data verification algorithm based on multiple verifiers and multiple challenges to reduce the verification overhead. The algorithm dynamically schedules the multiple verifiers' challenges based on verification time and the frequent itemsets of duplicate verification data in challenge sets by applying FP-Growth algorithm, and computes the batch proofs of frequent itemsets. Then the challenges are split into two parts, i.e., duplicate data and unique data according to the results of data extraction. Finally, the proofs of duplicate data and unique data are computed and combined to generate a complete proof of every original challenge. Theoretical analysis and experiment evaluation show that the algorithm reduces the verification cost and ensures the correctness of the data integrity verification by flexible batch data verification.