• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.6
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• pp.533-540
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• 2012

Rubber laminated bearings with lead core are highly affected by changes in temperature because key materials which are rubber and lead have temperature dependencies. In this study, two full scale LRB(D800, S=5) are manufactured and temperature dependency tests on shear properties are accomplished. The shear properties at the 3rd cycle are used at $-10^{\circ}C$, $0^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$, $30^{\circ}C$, $40^{\circ}C$ respectively. The double shear configuration, simultaneously testing two pieces, is applied for compression shear test in order to minimize the friction effects due to the test machine, described in ISO 22762-1:2010. Characteristic strength, post-yield stiffness, effective stiffness, equivalent damping ratio are estimated and presented coefficient due to the temperature changes.

• Journal of the Society of Naval Architects of Korea
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• v.57 no.6
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• pp.365-372
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• 2020

Ice induced abrasion is known as a critical problem in concrete gravity based offshore structures, which are mainly used in the arctic regions. Although many researches on ice abrasion have been conducted for the last several decades, there still are some difficulties in designing concrete gravity based offshore structures against abrasion problem because there is no standardized method yet due to the uncertain physics involved in. This paper presents an experimental study for the evaluation of concrete abrasion characteristics due to ice friction on concrete surface. For the test, a testing machine capable of abrasion and friction was designed and produced, and standardized procedure was proposed to produce ice specimen used for abrasion test. For the experiment, compressive strength of the ice specimen were explored through a static compression test. Then the friction test between ice specimen and concrete surface was performed and friction coefficients were derived using measured vertical and horizontal forces. Dependency of friction coefficients on some test parameters were studied and discussed as well.

• Journal of the Korea Society of Computer and Information
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• v.27 no.12
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• pp.151-159
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• 2022

In this paper, we propose the standardization architecture and weapon-sensor simulator for efficient reliability test in combat system. To reduce man-month of reliability test, application with high dependency on other module is selected and apply FORM. The proposed standardization architecture extracts common, variable elements and design patterns, S.O.L.I.D principles were applied. The proposed weapon-sensor simulator implements essential functions by identifying highly dependent element of other modules and the information from equipment can be directly received without processing by using communication middleware. As a result, it can replace actual ship-mounted equipment. In addition, it is possible to reduce the consumption rate of human resources when perform reliability test and modification time can be shorted.

• 한국전산유체공학회:학술대회논문집
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• 2001.05a
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• pp.149-154
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• 2001

Parallel performance of a Myrinet based PC-cluster was tested and compared with a conventional Fast-Ethernet system. A preconditioned Navier-Stokes code was parallelized with domain decomposition technique, and used for the parallel performance test. Speed-up ratio was examined as a major performance parameter depending on the number of processor and the network topology. As was expected, Myrinet system shows a superior parallel performance to the Fast-Ethernet system even with a single network adpater for a dual processor SMP machine. A test for the dependency on problem size also shows that network communication speed is a crucial factor for parallelized computational fluid dynamics analysis and the Myrinet system is a plausible candidate for high performance parallel computing system.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.8
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• pp.39-48
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• 1997

The fast redundancy identification is required to perform an efficient test pattern genration. Due to the reconvergent fanouts which make the dependency among objectives and the fault propagation blocking, there may exist redundnat faults in the cirucit. This paper presents the isomorphism identification and the pseudo dominator algorithms which are useful to identify redundant faults in combinational circuits. The isomorphism identification algorithm determines whether mandatory objectives required for fault detection cannot be simultaneously satisfied from primary input assignments or not using binary decision diagrma. The pseudo dominator algorithm determines whether faults propagation is possible or not by considering all paths at a given fanout node. Several experiments using ISCAS 85 benchmark circuits demonstrate the efficiency and practicability of the algorithms.

• The Korean Journal of Applied Statistics
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• v.9 no.1
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• pp.17-29
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• 1996

Suppose we have g itesm classified as defective or as nondefective. If we test each item separately, then g tests are required. However, it is possible to test a group of g items so as to detect whether at least one of them is defective, and to proceed to individual testing only if the presense of at least one defective item is indicated. The method is called Dorfman procedure. In this paper, we consider a variant of Dorfman procedure called a hierarchal dorfman procedure. We also consider the curtailment effect resulted from the dependency of the tests. We propose an efficient blood testing procedure. We also present ot heuristic rule of thumb which is simple and easily implementable.

• Journal of Korean Institute of Industrial Engineers
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• v.28 no.4
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• pp.351-359
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• 2002

In this paper, stochastically dependent single and sequential acceptance sampling plans are dealt when the process follows a Polya process model. A Monte-Cairo algorithm is used to find the acceptance and rejection probabilities of a lot. The number of defectives for the test to be accepted and rejected in a probability ratio sequential test can be found by using these probabilities. The formula to measure performance of these sampling plans is developed. Type I and II error probabilities are estimated by simulation. Dependent multiple acceptance sampling plans can be derived by extending the sequential sampling procedure. In numerical examples, single and sequential sampling plans of a Polya dependent process are examined and the characteristics are compared according to the change of the dependency factor.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.5
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• pp.734-738
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• 2010

Object Generator is a software to provide simulation object data(aircraft, ship, submarine, missile, torpedo) for sumulators in LBTS(Land Based Test System). but there is a burden to the system, because Object generator needs to send many object's data, display objects in a tactical screen, show object's information in a list in 1 second. This paper suggests a parallel software structure taking a few factors(deadlock, dependency) into consideration. At last, the paper shows the performance of the parallel structure's software compared with the former structure's software.

• Journal of the Korean Home Economics Association
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• v.34 no.2
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• pp.31-42
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• 1996

The purpose of this study was to examine the mother's perception on the concrete pattern of such behavior problems as noncompliance, jealousy, dependency, hyperactivity and stealing, by analyzing the difference between two cases of her own child and another mother's child relating to her attribution to the behavior problem of the child and the relationship between her attribution and behavioral reaction. This study was carried out by using 515 questionnaires answered by 1000 mothers of children of 7 kindergartens in Ulsan and Taegu, using Melissa Sweitzer's method (1986). The data was subjected to t-test, Pearson's correlation coefficient. T-test was applied to test the difference between two cases of her own child and another mother's child relating to her attribution to the behavior problem of the child and Person's correlation coefficient was estimated to test the relationship between her attribution and behavioral reaction. The result of this study is sumarized as follows : 1. It was shown that the mother's attribution to the behavior problem of the child is less serious when her child showed the behavior problem than when another child dose the problem while her attribution has an affective reaction to the behavior problem of the child. 2. The relationship between the mother's attribution and behavior reaction to the behavior problem of the child appeared variously in accordance with the attribution factor and behavior problem. Then the mother showed more attribution to stability while frequently ignoring the child.

• The Transactions of the Korea Information Processing Society
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• v.6 no.12
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• pp.3523-3529
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• 1999

In this paper, we propose an improved regression testing method, which use method as the basic unit of changing. The testing method consists of three steps. We represent the relationship of classes using the notation of UML(Unified Modeling Language), find the nodes of the modified methods and affected methods by node analysis, and then select changed test cases from the original test cases. The proposed object-oriented regression testing method can reduce the number of test cases, testing time and cost through reuse of test cases.