• Structural Engineering and Mechanics
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• 제86권6호
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• pp.705-714
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• 2023

In order to establish a dynamic model test method of bridge pylons subjected to ocean waves, the similarity method of hydroelastic model test for bridge pylons were analyzed systematically, and a model design and production method was proposed. Using this method, a dynamic test model of a bridge pylon was made, and then a free vibration test on the model structure and a dynamic response test of the model structure under wave actions were conducted in a wave flume. The results of the free vibration test show that the primary natural frequencies of the structure by the model test are close to the design frequencies of the prototype structure, indicating that the dynamic characteristics of the bridge pylon are well simulated by the model structure. The results of the dynamic response test show that wave induced base shear forces and motion responses on the model structure are consistent with the numerical results of the prototype structure. The model test results confirm that the proposed model test design method is feasible and applicable. It has application and reference significances for model testing studies of such marine bridge structures.

• 한국군사과학기술학회지
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• 제27권2호
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• pp.203-212
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• 2024

This paper describes the establishment of defense systems test works architecture model for the efficient operation of an expanded test organization and the provision of standardized test services after the integration of proving grounds in ADD. The system engineering vee model is applied to the defense system test works to define the project management model and the unit-test management model. In order to establish the defense systems test works architecture model, the process flow of test works, artifacts by life cycle, and interrelations between regulations and test works are explained, and Integrated Test Information System for implementation of architecture model is discussed. Through the defense systems test works architecture model presented in this study, it will contribute to quickly responding to the test requirements of complex and diverse defense systems, efficiently managing projects, and providing standardized test services.

• 대한조선학회논문집
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• 제51권5호
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• pp.349-355
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• 2014

The resistance test of a high speed craft such as planing ship is performed with a high speed towing carriage instead of ordinary towing carriage because of the speed limitation. In the resistance test using high speed towing carriage, the model ship is fixed to the carriage to restrain the running attitude for enough measuring time. Such method is called fixed model test method. In the fixed model test method, to get the appropriate running attitude, the model test is iteratively repeated until the trim moment and lift force are close to zero. In this research, trim free model test method is investigated to reduce the number of iteration. And, the limitation of towing speed range in the trim free model test method is investigated.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2002년도 추계학술대회 논문집
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• pp.134-141
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• 2002

A series of forced oscillation test on model mooring chain was carried out to investigate dynamic tension characteristics. The model test was conducted at two different water depth to gather basic data for 'truncated mooring test' and 'hybrid mooring test'. The truncated and hybrid mooring test are highly recommended to overcome the limitation of water depth in model test recently. The resultant tension RAO gives good possibility of approximation of dynamic tension by equivalent weight adjustment for the ratio of water depth in different water depth. Because the hybrid mooring test is the adequate combination of model test and simulation, accurate simulation model on mooring system is essential. The simulation results show good agreement with model test results.

• International Journal of Computer Science & Network Security
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• 제21권12spc호
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• pp.549-555
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• 2021

Machine Learning(ML) splits data into 3 parts, which are usually 60% for training, 20% for validation, and 20% for testing. It just splits quantitatively instead of selecting each set of data by a criterion, which is very important concept for the adequacy of test data. ML measures a model's accuracy by applying a set of validation data, and revises the model until the validation accuracy reaches on a certain level. After the validation process, the complete model is tested with the set of test data, which are not seen by the model yet. If the set of test data covers the model's attributes well, the test accuracy will be close to the validation accuracy of the model. To make sure that ML's set of test data works adequately, we design an experiment and see if the test accuracy of model is always close to its validation adequacy as expected. The experiment builds 100 different SVM models for each of six data sets published in UCI ML repository. From the test accuracy and its validation accuracy of 600 cases, we find some unexpected cases, where the test accuracy is very different from its validation accuracy. Consequently, it is not always true that ML's set of test data is adequate to assure a model's quality.

• Elastomers and Composites
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• 제51권4호
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• pp.308-316
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• 2016

The rubber materials are widely used in automobile industry due to their capability of a large amount of elastic deformation under a force. Current trend of design process requires prediction of functional properties of parts at early stage. The behavior of rubber material can be modeled using strain energy density function. In this study, five different strain energy density functions - Neo-Hookean model, Reduced Polynomial $2^{nd}$ model, Ogden $3^{rd}$ model, Arruda Boyce model and Van der Waals model - were used to estimate the behavior of carbon black added natural rubber under uniaxial load. Two kinds of tests - uniaxial tension test and biaxial tension test - were performed and used to correlate the coefficients of the strain energy density function. Numerical simulations were carried out using finite element analysis and compared with experimental results. Simulation revealed that Ogden $3^{rd}$ model predicted the behavior of carbon added natural rubber under uniaxial load regardless of experimental data selection for coefficient correlation. However, Reduced Polynomial $2^{nd}$, Ogden $3^{rd}$, and Van der Waals with uniaxial tension test and biaxial tension test data selected for coefficient correlation showed close estimation of behavior of biaxial tension test. Reduced Polynomial $2^{nd}$ model predicted the behavior of biaxial tension test most closely.

• Journal of the Korean Data and Information Science Society
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• 제27권2호
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• pp.559-564
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• 2016

The Durbin-Watson (DW) test in regression model and the Ljung-Box (LB) test in ARMA (autoregressive moving average) model are typical examples of correlated error tests. The DW test is used for detecting autocorrelation of errors using the residuals from a regression analysis. The LB test is used for specifying the correct ARMA model using the first some sample autocorrelations based on the residuals of a tted ARMA model. In this article, simulations with four data generating processes have been carried out to evaluate their performances as correlated error tests. Our simulations show that the DW test is severely dependent on the assumed AR(1) model but isn't sensitive enough to reject the misspecified model and that the LB test reports lackluster performance in general.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제8권6호
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• pp.235-242
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• 2019

본 논문에서는 제어기 기능이 표현 된 변경된 MATLAB Simulink/Stateflow(SL/SF) 모델의 재사용 가능한 테스트 케이스 도출 기법을 제안한다. 자동차의 ECU(Electrical Control Unit)와 같이 복잡한 SL/SF 모델의 테스트 케이스를 작성하는데 많은 시간과 노력이 필요하다. 모델이 수정 될 때마다 새로 만들어낼 테스트 케이스를 줄이기 위한 직관적인 방법은 수정 전 모델에서 생성한 테스트 케이스 중 일부를 재사용하는 것이다. 본 논문에서는 모델 행동을 정의하고 테스트 케이스 별 모델 동등성을 판단하여 수정 후 SL/SF에 재사용 가능한 테스트 케이스를 도출하는 방법을 제안한다. 제안된 테스트 케이스 재사용 기법은 상용 자동차 제어기 모델을 이용하여 성능을 평가한다.

• 한국환경과학회지
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• 제9권1호
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• pp.35-42
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• 2000

In this study, the movable bed model testing was carried out so as to analyze bed profile changes including predicting scouring and deposition of bed profile and to solve hydraulic problems affecting with bed and both-bank between upstream and downstream of intake weir in the Nakdong river channel. The movable bed model testing consists of fundamental test, movable model test and numerical analysis method respectively. The fundamental test was enforced to analyze relationship of discharge and sediment load in the tilting flume. When the movable model test was worked, it was shown that sediment budget between input sediment load and output sediment load was balanced exactly. As a result of movable model test, it was presented that scouring and deposition changes in quantities between the upstream and downstream of modification weir were less than those of nature and planning weir. Finally, numerical analysis method was operated by 1-dimensional bed profile changes model ; HEC-6 model so as to complement unsolving hard problems during movable model test. So, modification weir will sustained the stable bed profile changes than any other weirs in the study channel.

• 정보처리학회논문지D
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• 제14D권1호
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• pp.57-66
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• 2007

소프트웨어 산업의 발전에 따라 소프트웨어 개발조직에서는 소프트웨어 품질이 중요한 이슈로 부각되었다. 특히 여러 종류의 테스트 성숙도 모델을 통해 조직의 소프트웨어 테스트 성숙도 향상에 대해 다양한 방면으로 시도하고 있다. 하지만 현재 테스트 성숙도를 측정할 수 있는 모델들은 기존의 개발 성숙도 측정 모델을 기반으로 개발하여 테스트 부분에 대한 언급이 부족하고 단지 테스트 성숙도 레벨만을 측정하였다. 이러한 문제점을 해결하기 위해 소프트웨어 개발프로세스와 한께 테스트 프로세스를 수행할 수 있도록 이중 V모델과 테스트 성숙도의 용이한 평가를 위한 테스트 평가 속성과 레벨을 정의한 테스트 속성과 상호관련 매트릭스를 제안하였다. 테스트 프로세스 개선(Test Process Improvement: TPI)의 개선제안(Improvement Suggestion) 방법을 통해 테스트 성숙도 모델 확장하고, 측정된 성숙도를 향상시킬 수 있는 개선방향을 제시한다. 또한, 본 연구에서 제안하는 테스트 성숙도 상호관련 매트릭스는 테스트 성숙도를 정량적으로 평가하기 위해 사용하였다. 결과적으로는 확장된 테스트 성숙도 모델을 통해 조직의 테스트 성숙도를 높이는데 기여 할 수 있으리라 생각한다.