• Title/Summary/Keyword: Consistency Checks

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Issues When Estimating Fatigue Life of Structures

  • Lee, Ouk-Sub;Chen, Zhi-wei
    • International Journal of Precision Engineering and Manufacturing
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    • v.1 no.2
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    • pp.43-47
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    • 2000
  • When estimating fatigue crack growth (FCG) life of structures, the use of crack growth models and knowledge of the values of their corresponding parameters are of vital importance. Inconsistency in using models with appropriate parameters can lead to enormous errors in FCG life prediction. In this paper examples are analyzed and compared with test results to show the possible problems, Consistency checks are necessary for avoiding some pitfalls, and also necessary for verifying the correct performance and accuracy of the used computer program.

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Four Consistency Levels in Trigger Processing (트리거 처리 4 단계 일관성 레벨)

  • ;Eric Hanson
    • Journal of KIISE:Databases
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    • v.29 no.6
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    • pp.492-501
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    • 2002
  • An asynchronous trigger processor (ATP) is a oftware system that processes triggers after update transactions to databases are complete. In an ATP, discrimination networks are used to check the trigger conditions efficiently. Discrimination networks store their internal states in memory nodes. TriggerMan is an ATP and uses Gator network as the .discrimination network. The changes in databases are delivered to TriggerMan in the form of tokens. Processing tokens against a Gator network updates the memory nodes of the network and checks the condition of a trigger for which the network is built. Parallel token processing is one of the methods that can improve the system performance. However, uncontrolled parallel processing breaks trigger processing semantic consistency. In this paper, we propose four trigger processing consistency levels that allow parallel token processing with minimal anomalies. For each consistency level, a parallel token processing technique is developed. The techniques are proven to be valid and are also applicable to materialized view maintenance.

Consistency check algorithm for validation and re-diagnosis to improve the accuracy of abnormality diagnosis in nuclear power plants

  • Kim, Geunhee;Kim, Jae Min;Shin, Ji Hyeon;Lee, Seung Jun
    • Nuclear Engineering and Technology
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    • v.54 no.10
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    • pp.3620-3630
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    • 2022
  • The diagnosis of abnormalities in a nuclear power plant is essential to maintain power plant safety. When an abnormal event occurs, the operator diagnoses the event and selects the appropriate abnormal operating procedures and sub-procedures to implement the necessary measures. To support this, abnormality diagnosis systems using data-driven methods such as artificial neural networks and convolutional neural networks have been developed. However, data-driven models cannot always guarantee an accurate diagnosis because they cannot simulate all possible abnormal events. Therefore, abnormality diagnosis systems should be able to detect their own potential misdiagnosis. This paper proposes a rulebased diagnostic validation algorithm using a previously developed two-stage diagnosis model in abnormal situations. We analyzed the diagnostic results of the sub-procedure stage when the first diagnostic results were inaccurate and derived a rule to filter the inconsistent sub-procedure diagnostic results, which may be inaccurate diagnoses. In a case study, two abnormality diagnosis models were built using gated recurrent units and long short-term memory cells, and consistency checks on the diagnostic results from both models were performed to detect any inconsistencies. Based on this, a re-diagnosis was performed to select the label of the second-best value in the first diagnosis, after which the diagnosis accuracy increased. That is, the model proposed in this study made it possible to detect diagnostic failures by the developed consistency check of the sub-procedure diagnostic results. The consistency check process has the advantage that the operator can review the results and increase the diagnosis success rate by performing additional re-diagnoses. The developed model is expected to have increased applicability as an operator support system in terms of selecting the appropriate AOPs and sub-procedures with re-diagnosis, thereby further increasing abnormal event diagnostic accuracy.

A Study on design of The Internet-based scoring system for constructed responses (서답형 문항의 인터넷 기반 채점시스템 설계 연구)

  • Cho, Ji-Min;Kim, Kyung-Hoon
    • The Journal of Korean Association of Computer Education
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    • v.10 no.2
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    • pp.89-100
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    • 2007
  • Scoring the constructed responses in large-scale assessments needs great efforts and time to reduce the various types of error in Paper-based training and scoring. For the purpose of eliminating the complexities and problems in Paper and pencil based training and scoring, many of countries including U.S.A and England already have applied online scoring system. There, however, has been few studies to develop the scoring system for the constructed responses items in Korea. The purpose of this study is to develop the basic design of the Internet-based scoring system for the constructed responses. This study suggested the algorithms for assigning scorers to constructed responses, employing methods for monitoring reliability, etc. This system can ensure reliable, quick scoring such as monitor scorer consistency through ongoing reliability checks and assess the quality of scorer decision making through frequent various checking procedures.

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A Concurrency Control Method for Data Broadcasting in Mobile Computing Environment (이동 컴퓨팅 환경에서 데이타 방송을 위한 동시성 제어 기법)

  • 윤혜숙;김영국
    • Journal of KIISE:Databases
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    • v.31 no.2
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    • pp.140-149
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    • 2004
  • Data broadcast has received much attention as a very efficient method for disseminating data items in mobile environment with large number of mobile clients. In this approach, a database server periodically and continuously broadcasts data items through wireless channels and clients perform read-only transactions by accessing necessary data items from the air. While broadcasting, the server must also process update transactions on the database, which raises an obstacle for client's accessing consistent data. In this research, we propose a new algorithm SCDSC(Serialization Checking with DirtySet on Commit) which is an alternative for solving the concurrency control problem efficiently. The SCDSC is a kind of optimistic concurrency control in that a client checks the consistency of data using a DirtySet as a part of data broadcast when it commits its transaction. In each broadcast cycle, the server updates and disseminates the DirtySet with newly changed data items for last few cycles in the sliding window approach. We perform an analysis and a simulation study to evaluate the performance of our SCDSC algorithm in terms of data consistency and data currency.

USING TABU SEARCH IN CSPS

  • Gupta, D.K.
    • Journal of applied mathematics & informatics
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    • v.8 no.1
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    • pp.181-197
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    • 2001
  • A heuristic method TABU-CSP using Tabu Search (TS) is described for solving Constraint Satisfaction Problems (CSPs). The method is started with a complete but inconsistent solution of a binary CSP and obtained in prespecified number of iterations either a consistent solution or a near optimal solution with an acceptable number of conflicts. The repair in the solution at each iterative step is done by using two heuristics alternatively. The first heuristic is a min-conflicts heuristic that chooses a variable with the maximum number of conflicts and reassigns it the value which leads to the minimum number of conflicts. If the acceptable solution is not reached after the search continued for a certain number of iterations, the min-conflict heuristic is changed and the variable selected least number of times is chosen for repair. If an acceptable solution is not reached, the method switches back to the min-conflict heuristic and proceeds further. This allowed the method to explore a different region of search space space for the solution as well as to prevent cycling. The demonstration of the method is shown on a toy problem [9]which has no solution. The method is then tested on various randomly generated CSPs with different starting solutions. The performance of the proposed method in terms of the average number of consistency is checked and the average number of conflicts is conflicts is compared with that of the Branch and Bound(BB) method used to obtain the same solution. In almost all cases, the proposed method moves faster to the acceptable solution than BB.

A Behavior Conformance Checker for Component Interfaces using UML State Machine Diagram (UML 상태기계 다이어그램을 이용한 컴포넌트 인터페이스의 행위 호환성 검증 도구)

  • Kim, Ho-Jun;Lee, Woo-Jin
    • The KIPS Transactions:PartD
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    • v.16D no.1
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    • pp.65-72
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    • 2009
  • Component based development has increasingly become important in the software industry. However, in the current component based development approach with UML, the absence of behavioral description of components brings about a cost problem which causes semantic errors on the testing phase. Accordingly we cannot grasp the usage pattern of component by its provided interfaces which refer to an abstraction of software component. And we cannot guarantee the behavioral conformance of the provided and required interfaces of components. In order to solve these problems, we describe the behaviors of component interfaces by state machine diagram and guarantee their behavior conformance at the modeling phase. We also propose a method to guarantee the behavior conformance of component interfaces with concept of observation equivalence and invocation consistency. And we provide an analyzing tool which checks interface behavior conformance.

A Validation Study of the Korean Version of the Connectedness to Nature Scale

  • Gim, Wan-Suk;Lee, Min-Hyung;Kim, Kwang-Hyune
    • Journal of People, Plants, and Environment
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    • v.22 no.6
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    • pp.621-628
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    • 2019
  • The purpose of this study was to investigate the reliability and validity of the Korean version of the Connectedness to Nature Scale(K-CNS), which was translated from the Connectedness to Nature Scale(CNS) developed by Mayer and Frantz. For this study, questionnaires were conducted with a sample of 407 Korean citizens from various backgrounds and regions, with the ages ranging from 17 to 60. Exploratory factor analysis, internal consistency test and correlation checks were conducted on this questionnaires data. The results of exploratory factor analysis supported that the K-CNS has 10 items in a single factor. The internal consistency of the K-CNS was .880. The K-CNS was positively correlated to the NEP (New Environmental Paradigm), satisfaction with life, mental health, compassionate love, and negatively correlated to stress response. In addition, differences were found by group and age, but not by the gender. The K-CNS was higher in the natural-friendly group than in the general group. By age, the K-CNS scores was high in 40s and 50s than 10-39 years old.

Performance Analysis on GPS RAIM in the Post SA Era

  • Choi, Jae-Won;Lee, Jang-Gyu;Park, Chan-Gook;Jee, Gyu-In
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.56.4-56
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    • 2001
  • Using GPS in the navigation systems such as aviation, maritime and land applications, integrity is considered importantly with accuracy for safety. Integrity monitoring performed in the GPS receiver itself is Receiver Autonomous Integrity Monitoring (RAIM) and need not an independent ground monitoring station. RAIM algorithm uses redundant information when more than four satellites are visible and makes consistency checks between measurement information to alarm users whether the system is operating out of its specified performance limits. Selective Availability (SA) that was used to protect the security interests of the U.S. and its allies by globally denying the full accuracy of the civil system was turned off on May 1, 2000 ...

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Formal Analysis of Automatic Train Protection and Block System for Regional Line Using VDM++

  • Xie, Guo;Hei, Xinhong;Mochizuki, Hiroshi;Takahashi, Sei;Nakamura, Hideo
    • International Journal of Railway
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    • v.5 no.2
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    • pp.65-70
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    • 2012
  • This paper introduced a novel railway system, Automatic Train Protection and Block (ATPB) briefly, which is proposed to improve the efficiency of existing regional train lines with low cost in Japan. The biggest superiority of ATPB system is a great use of universal and mature technologies, such as GPS and regular mobile telephone networks, so that there is nearly no increment of trackside equipments in the reconstruction. Then in order to guarantee the system safety, a formal model of ATPB is established and analyzed by formal method VDM++. Firstly, the specification is specified by VDM++ formally without ambiguity. Secondly, its internal consistency is proved by discharging the proof obligations. And finally, its satisfiability is checked by systematic testing, which executes specification and checks the outputs against corresponding inputs.