• Journal of Biomedical Engineering Research
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• v.10 no.3
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• pp.261-268
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• 1989

The characteristics of aging of near-equiatomic Ni-Ti alloy has been studied by the three point bend test and the measurement of Differential Scanning Calorimetry(DSC). The DSC is used to measure precise transformation temperatures and the amount of thermal energy required for the corresponding phase transformation. The effort of hardness on aging treatment in saline solution of $37^{\circ}C$ was higher for the annealed than solution treated specimens. As the testing temperature inc- rease from under $M_f$ to above $A_f$ temperature, the elastic stiffness increased. Almost full recovery can be achieved after bending below Belo outer fiber strain. Total bend recovery decreased gradually as aging time and bend angle is increased.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.3
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• pp.18-26
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• 1999

소프트웨어 개발과정에서는 설계 및 코딩에 의해서 프로그램 내에 많은 결함이 삽입되고 시험을 거치는 동안 결함은 발견되고 수정되어 진다. 이와 같은 반복 작업을 통해서 소프트웨어 내에 잠재하고 있는 에러들을 발견, 조치함으로써 소프트웨어 품질은 향상되고 품질에 대한 신뢰성이 높아진다. 본 논문에서는 위와 같은 소프트웨어 개발 과정을 거치는 동안에 많은 시험이 동반되고 이에 따른 시험의 여러 자원이 투입되는데 착안하여 소프트웨어 신뢰도가 성장되어 가는 과정에 수반된 시험능력을 기반으로 한 시험능력의존형 소프트웨어 신뢰도 성장모델을 살펴보고 이를 적용하여 개발중인 소프트웨어에 대한 시험능력 투입에 따른 신뢰도를 평가하였다. 또 S-Shaped Model에 의한 평가치와 비교하여 시험이 진행됨에 따라 소프트웨어 고장 발견율이 상승되는 것을 보였다.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.15-18
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• 2003

Development of the construction industry generally exhausts natural aggregate. Hence it is problem to the lack of supply and quality deterioration, so the resource saving and protection of environment is made an effort through recycling by-product. This study presents that fundamental properties of concrete which used cooper slag as alternate sand of low fineness modulus and plan of cooper slag as concrete aggregate. Testing factors are concrete's slump, air contents, unit weight and compressive strength. The results of this study are as follows; (1) Concrete slump is generally satisfied with the condition but is inferior to the others in substitution rates 30%. Also air contents are 3.1-4.1% and go up according to increase substitution rate. (2) Unit weight increase in 1.1% as the mixing ratio of cooper slag argument 10%. (3) compressive strength of cooper slag concrete is similar to plain and especially higher 11-15% in W/C 45%, 50%. So it seems that aggregate mixed cooper slag is suitable to low water-cement ratio mixture.

• Proceedings of the IEEK Conference
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• 2003.11b
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• pp.35-38
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• 2003

지난 수십년간 많은 SRGM이 제안되었다. 이러한 모델들 중 많은 부분에서 암암리에 소프트웨어 테스트 전 단계를 거쳐서 테스트노력이 상수인 것으로 가정하거나 또는 아예 고려하지도 않았다. 그 후 몇몇 논문을 통하여 테스트노력을 고려한 소프트웨어의 신뢰도 평가가 중요한 인자인 것으로 발표되었다. 이들에 의해 지금까지 제안된 형태를 보면 지수함수형, 레일레이형, 웨이블형, 로지스틱형, 테스트노력함수로서 경우에 따라 이 중 하나의 적합한 형태를 사용해왔다. 본 논문에서는 이 네 가지 형태에 대해서 최소자승평가자(LSE)와 최대가능성평가자(MLE)를 써서 신뢰도 성장 파라미터를 구하는 방법에 대해서 고찰하고, 실제의 데이터를 적용하여 각각의 경우에 대한 파라미터를 구하고 이를 이용하여 목표신뢰도에 맞는 발행시기를 결정하는 문제를 연구하였다.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.3
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• pp.527-534
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• 1987

This paper proposes a new syndrome-testable design method for large MOSPLA's. In the conventional syndrome test method, the testing array circuit for testability is added but it has the defect that the circuit gives effect on the normal operation of the basic PLA circuit. Therefore, by adding the shift registers to the product lines of the basic MOSPLA's this defect is eliminated and the number of test patterns is decreased. In order to reduce the number of fault free syndromes to be predetermined, also, one output line, which is connected to all product lines is added. Therefore the number of output lines be observed is decreased. And the analytical method to compute fault free syndromes is presented. By unsing this method, the time and the effort to compute the syndromes are decreased.

• Wind and Structures
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• v.5 no.1
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• pp.1-14
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• 2002

Artificial Neural Networks (ANN) have the capability to develop functional relationships between input-output patterns obtained from any source. Thus ANN can be conveniently used to develop a generalised relationship from limited and sometimes inconsistent data, and can therefore also be applied to tackle the data obtained from wind tunnel tests on building models with large number of variables. In this paper ANN model has been developed for predicting wind induced pressures in various zones of a Gable Building from limited test data. The procedure is also extended to a case wherein interference effects on a gable roof building by a similar building are studied. It is found that the Artificial Neural Network modelling is seen to predict successfully, the pressure coefficients for any roof slope that has not been covered by the experimental study. It is seen that ANN modelling can lead to a reduction of the wind tunnel testing effort for interference studies to almost half.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.6
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• pp.9-18
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• 2000

This study includes noise automatic inspection system for washing machine auto-transmission one of modern home necessary. We effort to find and certificate sound noise source by sound power and sound intensity, and apply to frequency analysis in vibration related sound noise. still more we have been studying to data acquisition and programming for MS VisualBasic version 5.0. System component is below. 1) Pentium PC or data acquisition. 2) DSO for noise acquisition. 3)S/W for comparison and decision. 4) I/F Board for data communication. Wave form data through the DSO are converting to ASCII code data. The ASCII code through binary converting S/W. Finally we will making noise monitoring system and automatic inspection system.

• The Journal of Information Systems
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• v.8 no.1
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• pp.93-108
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• 1999

The switching system is designed and developed to satisfy the performance design objectives recommended by ITU for call processing capacity and quality of service(QOS), etc. When the results by actual measurement at the system testing phase do not satisfy the performance design objectives, however, an effort is required to improve the performance. This paper presents a method for improving QOS by modifying the application programs for the switching system. In the proposed method, the sequence chart related to a delay time for call connection is modelled using PERT(Program Evaluation and Review Technique) network. Then, the criticality index of a message is calculated using Monte Carlo simulation to evaluate which message's processing time to decrease in order to decrease the delay time and thus to improve QOS. The criticality index of a block is also calculated to identify those software blocks that significantly contribute to the delay time.

• Steel and Composite Structures
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• v.10 no.4
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• pp.331-348
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• 2010

Ample research effort has been oriented into developing damage indices with the aim of estimating in a reasonable manner the consequences, in terms of structural damage and deterioration, of severe plastic cycling. Although several studies have been devoted to calibrate damage indices for steel and reinforced concrete members; currently, there is a challenge to study and calibrate the use of such indices for the practical evaluation of complex structures. The aim of this paper is to introduce an energy-based damage index for multi-degree-of-freedom steel buildings that accounts explicitly for the effects of cumulative plastic deformation demands. The model has been developed by complementing the results obtained from experimental testing of steel members with those derived from analytical studies regarding the distribution of plastic demands on several steel frames designed according to the Mexico City Building Code. It is concluded that the approach discussed herein is a promising tool for practical structural evaluation of framed structures subjected to large energy demands.

• Journal of the Korean Data and Information Science Society
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• v.28 no.4
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• pp.875-888
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• 2017

The Rayleigh distribution has been commonly used in life time testing studies of the probability of surviving until mission time. We focus on a reliability function of the Rayleigh distribution and deal with prior distribution on R(t). This paper is an effort to obtain Bayes estimators of rayleigh distribution with three different prior distribution on the reliability function; a noninformative prior, uniform prior and inverse gamma prior. We have found the Bayes estimator and predictive density function of a future observation y with each prior distribution. We compare the performance of the Bayes estimators under different sample size and in simulation study. We also derive the most plausible region, prediction intervals for a future observation.