• Title/Summary/Keyword: Integrity verification

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Verification Test for Primary Reactor Piping in Nuclear Power Plant (원자로 주 배관계의 진동 건전성 시험)

  • Kim, Yeon-Whan;Kim, Hee-Su;Koo, Jae-Raeyang;Bea, Yong-Chae;Lee, Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11a
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    • pp.315.1-315
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    • 2002
  • The piping verification tests were performed in order to verify the structural integrity during initial operation of the reactor coolant systems and the primary heat transportation systems of nuclear power plants by KEPRI in Korea. The tests were conducted at full operating temperature and pressure. The objective is to evaluate the possibility of excessive load generating on piping, piping supports, and reactor structures etc. in the steady normal operation and expected pump transient conditions. (omitted)

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A Query Result Integrity Assurance Scheme Using an Order-preserving Encryption Scheme in the Database Outsourcing Environment (데이터베이스 아웃소싱 환경에서 순서 보존 암호화 기법을 이용한 질의 결과 무결성 검증 기법)

  • Jang, Miyoung;Chang, Jae Woo
    • Journal of KIISE
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    • v.42 no.1
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    • pp.97-106
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    • 2015
  • Recently, research on database encryption for data protection and query result authentication methods has been performed more actively in the database outsourcing environment. Existing database encryption schemes are vulnerable to order matching and counting attack of intruders who have background knowledge of the original database domain. Existing query result integrity auditing methods suffer from the transmission overhead of verification object. To resolve these problems, we propose a group-order preserving encryption index and a query result authentication method based on the encryption index. Our group-order preserving encryption index groups the original data for data encryption and support query processing without data decryption. We generate group ids by using the Hilbert-curve so that we can protect the group information while processing a query. Finally, our periodic function based data grouping and query result authentication scheme can reduce the data size of the query result verification. Through performance evaluation, we show that our method achieves better performance than an existing bucket-based verification scheme, it is 1.6 times faster in terms of query processing time and produces verification data that is 20 times smaller.

Study on Evaluation Method of Structural Integrity for Cone-Type Composite Lattice Structures with Hexagonal Cell (육각 격자구조를 갖는 콘형 복합재 격자구조체의 구조안전성 평가 기법 연구)

  • Im, Jae-Moon;Kang, Seung-Gu;Shin, Kwang-Bok;Lee, Sang-Woo
    • Composites Research
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    • v.31 no.4
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    • pp.156-160
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    • 2018
  • In this paper, evaluation method of structural integrity for cone-type composite lattice structures with hexagonal cell was conducted. A finite element analysis was used to evaluate the structural integrity of cone-type composite lattice structure. The finite element model for evaluation of structural integrity was generated using solid element. In order to consider the difference in mechanical properties between intersection and non-intersection part, the mechanical properties were applied considering the fiber volume fraction of each part. Compression test of cone-type composite lattice structure were conducted for verification of evaluation method of structural integrity. The analysis result showed 2% errors in displacement and good agreement with test result.

Development of Feedback Data Automated Verification Program for Mission S/W (임무 S/W 시험을 위한 피드백 데이터의 기댓값 검증 자동화 도구 개발)

  • Kwon, GI-Bong;Lee, Ha-Yoeun;Ha, Seok-Wun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.49 no.10
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    • pp.871-877
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    • 2021
  • Aircraft defects are important matters directly related to the operation of the aircraft and the life of the pilot. The defects in the mission software that occur during aircraft control seriously affect the pilot's mission performance and safety. Therefore, the organization in charge of aircraft development or software defects are reinforced in the process to identify and eliminate defects in the early stages of development, and a lot of labor and time are spent, but due to the nature of the mission software, strong functional coupling with other avionics and high complexity, so there are restrictions on the identification and removal of software defects through the existing test method. This study analyzes the effect of securing mission software integrity and reducing test cost through data integrity verification by developing a tool that automates the verification of expected value of feedback data among communication data of mission computer interlocking equipment.

Evaluation of recent changes in genetic variability in Thoroughbred horses based on microsatellite markers parentage panel in Korea

  • Park, Chul Song;Lee, Sun Young;Cho, Gil Jae
    • Animal Bioscience
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    • v.35 no.4
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    • pp.527-532
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    • 2022
  • Objective: In this study, we aimed to investigate the recent changes such as allele frequencies and total probability of exclusion (PE) in Thoroughbred horses in Korea using short tandem repeat (STR) parentage panels between 2006 and 2016. Methods: The genotype was provided for 5,988 horse samples with 15 microsatellite markers (AHT4, AHT5, ASB2, ASB17, ASB23, CA425, HMS1, HMS2, HMS3, HMS6, HMS7, HTG4, HTG10, LEX3 and VHL20). Results: In our study, the observed number of alleles per locus ranged from 3 (HMS1) to 9 (ASB17) in 2006 and 4 (HMS1) to 9 (ASB2) in 2016, with a mean value of 6.28 and 6.40, respectively. Of the 15 markers, HMS2, HTG4, and CA425 loci had relatively low polymorphism information content (<0.5000) in the Thoroughbred population. Mean levels of genetic variation in 2006 and 2016 were observed heterozygosity (HO) = 0.708, and expected heterozygosity (HE) = 0.685, as well as and HO = 0.699 and HE = 0.682, respectively. The PE was calculated for each group based on the allele frequencies of 14 or 15 STRs. The 2006 survey analyzed that PE was 0.9998, but it increased to 0.9999 in 2016 after the HMS2 marker was added in 2011. The current STR panel is still a powerful tool for parentage verification that contributes to the maintenance of integrity in the Thoroughbred population. Conclusion: The current STR panel is still a powerful tool for parentage verification that contributes to the maintenance of integrity in the Thoroughbred horses. However, continuous monitoring genetic variability is necessary.

An Efficient Broadcast Authentication Scheme with Batch Verification for ADS-B Messages

  • Yang, Haomiao;Kim, Hyunsung;Li, Hongwei;Yoon, Eunjun;Wang, Xiaofen;Ding, Xuefeng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.10
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    • pp.2544-2560
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    • 2013
  • As a cornerstone of the next generation air traffic management (ATM), automatic dependent surveillance-broadcast (ADS-B) system can provide continual broadcast of aircraft position, identity, velocity and other messages over unencrypted data links to generate a common situational awareness picture for ATM. However, since ADS-B messages are unauthenticated, it is easy to insert fake aircrafts into the system via spoofing or insertion of false messages. Unfortunately, the authentication for ADS-B messages has not yet been well studied. In this paper, we propose an efficient broadcast authentication scheme with batch verification for ADS-B messages which employs an identity-based signature (IBS). Security analysis indicates that our scheme can achieve integrity and authenticity of ADS-B messages, batch verification, and resilience to key leakage. Performance evaluation demonstrates that our scheme is computationally efficient for the typical avionics devices with limited resources, and it has low communication overhead well suitable for low-bandwidth ADS-B data link.

A Study on the SIL Allocation and Demonstration for Train Control System (열차제어시스템 SIL할당 및 입증에 관한 연구)

  • Shin, Duc-Ko;Baek, Jong-Hyen;Lee, Kang-Mi;Lee, Jae-Ho
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.855-859
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    • 2009
  • In this paper, we introduce the estimation method by Risk or SIL(Safety Integrity Level) for the criterion of safety assurance and summarize each application method and target. IEC 62278(EN 50126) which is international standard for the specification and verification of the railway system RAMS indicate a criterion of safety assurance. Especially, it recommend the safety verification by continuous verification as the order of requirement establishment, design, manufacture, installation, operation, and maintenance for the equipment not easy to quantify the operation environment. In this paper, we study the SIL requirement allocation method relating to internal new system development and existing system improvement by analysing SIL recommendations which were used to understand SIL for a train control equipment in 1990s in IRSE and theoretically their allocation background. This paper help the safety management of Korea train control system to develope the quantitative management procedure as international level by analyzing the SIL requirement allocation by operation agency and the right SIL verification procedure by manufacture and indicating the example to assure safety because it is necessary for improvement and localization for the Korea train control system having highly dependence on aboard technology.

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Scale Development on Health Conservation of the Institutionalized Elderly (시설 노인의 건강보존에 관한 도구 개발)

  • Sung, Ki-Wol
    • Journal of Korean Academy of Nursing
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    • v.35 no.1
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    • pp.113-124
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    • 2005
  • Purpose: The purpose of this study was to develop a health conservation scale with high validity and reliability for institutionalized elderly. Method: The process of development of this scale was as follows. A conceptual framework composed of 4 phases of health conservation of institutionalized elderly was identified based on the literature review with elderlies and discussions with experts in health conservation. A total of 75 items, on a 4-point scale were developed. Through reliability testing and factor analysis, 57 preliminary items were selected. By means of internal consistency of the 57 items, 18 items whose inner-items correlation coefficient was below .40 were deleted. Through factor analysis, 2 items whose factor loading was below .40 were deleted. Finally 37 items remained. To verity the 37 items, factor analysis, reliability testing, and correlation was done. Data were collected from 207 institutionalized elderly subjects in Daegu, Kyungpook, Busan, and KyungNam Province from August. 2003 to February. 2004. Result: In the result of factor analysis of the 37 items, 4 factors were extracted. These factors were labeled as ‘personal integrity’, ‘conservation of energy', ‘structural integrity’, and ‘social integrity'. These factors included 4 phases of health conservation. Cronbach's Alpha of 37 the items was .9424 and the correlation coefficient of HPLP was .723. Conclusion: The researchers recommend the following: An explorative study on the variables related to health conservation is needed for criterion validity of this scale. Studies on health conservation of different age groups, and subjects are needed for verification.

Probabilistic Damage Mechanics Assessment of CANDU Pressure Tube using Genetic Algorithm (유전자 알고리즘을 이용한 CANDU 압력관의 확률론적 손상역학 평가)

  • Ko, Han-Ok;Chang, Yoon-Suk;Choi, Jae-Boong;Kim, Young-Jin;Kim, Hong-Key;Choi, Young-Hwan
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.192-192
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    • 2008
  • As the lifetime of nuclear power plants (NPPs) reaches design life, the probability for fatal accidents increases. Most of accidents are known to be caused by degradation of mechanical components. Pressure tubes are the most important components in CANDU reactor. They are subjected to various aging mechanisms such as delayed hydride cracking (DHC), irradiation and corrosion, etc. Therefore, the integrity of pressure tube is key concern in CANDU reactor. Up to recently, conventional deterministic approaches have been utilized to evaluate the integrity of components. However, there are many uncertainties to prevent a rational evaluation. The objective of this paper is to assess the failure probability of pressure tube in CANDU. To do this, probability fracture mechanics (PFM) analysis based on the Genetic Algorithm (GA) is performed. For the verification of the analysis, a comparison of the PFM analysis using a commercial code and mathematical method is carried out.

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Application of Probabilistic Fracture Mechanics Technique Using Monte Carlo Simulation (몬테카를로 시뮬레이션을 이용한 확률론적 파괴역학 수법의 적용성 검토)

  • Lee, Joon-Seong;Kwak, Sang-Log;Kim, Young-Jin
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.10
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    • pp.154-160
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    • 2001
  • For major structural components periodic inspections and integrity assessments are needed for the safety. However, many flaws are undetectable because sampling inspection is carried out during in-service inspection. Probabilistic integrity assessment is applied to take into consideration of uncertainty and variance of input parameters arise due to material properties and undetectable cracks. This paper describes a Probabilistic Fracture Mechanics(PFM) analysis based on the Monte Carlo(MC) algorithms. Taking a number of sampling data of probabilistic variables such as fracture toughness value, crack depth and aspect ratio of an initial surface crack, a MC simulation of failure judgement of samples is performed. for the verification of this analysis, a comparison study of the PFM analysis using a commercial code, mathematical method is carried out and a good agreement was observed between those results.

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