• 제목/요약/키워드: model test

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축소형 풍력터빈 풍동시험-축소효과 보상기법 (Wind Tunnel Test for Scaled Wind Turbine Model (Scale effect correction))

  • 조태환;김양원;박영민;장병희
    • 신재생에너지
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    • 제4권2호
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    • pp.87-93
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    • 2008
  • Wind tunnel test for the 12% scaled model of NREL Phase VI wind turbine was conducted in KARI low speed wind tunnel for $2006{\sim}2007$. The 1st and 2nd test was designed to find out the wind tunnel test method for the blade manufacturing accuracy and surface treatment method by using the composite and aluminum blades. And the 3rd test was designed to study the scale effect. The chord extension method which was used for Bo-105 40% scaled model was adapted for scale effect correction. Test results shows that the chord extension method works well for the torque slope but the maximum torque for scaled model is about 8% below than the real scale model. New correction method to correct this offset was proposed.

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Soil-Bentonite 혼합토의 투수 특성 연구 (A on Permeability Characteristics of Soil-Bentonite Mixture)

  • 임은상;신동훈;조성은;김재홍
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 춘계 학술발표회
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    • pp.852-857
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    • 2009
  • Recently the centrifuge test has been used increasingly to clarify a problem of seepage in dam. However, one of the most difficult challenges in the testing is to conform permeability properties of model ground to the prototype. In order to resolve the problem, a few solutions, such as an increase of pore water viscosity and a regulation of water permeability, are suggested. Although the use of prototype materials is principles if a model test is carried out, the materials of similarity gradation is used in the centrifuge model test because of the nature of the model test for dam. Therefore, we choose the latter method for model ground materials. In this study, the permeability properties of soil-bentonite mixtures are studied through the permeation test using triaxial compaction test apparatus.

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압축공기 발사기에 단선 와이어 유도방식을 적용한 1/60축척 터널주행 열차모형 시험기 개발에 대한 연구 (Development of 1/60th Scale Moving Model Rig Using the Compressed Air Launcher and One-Wire Guidance System of Train Model)

  • 김동현;오일근
    • 대한기계학회논문집B
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    • 제25권5호
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    • pp.634-644
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    • 2001
  • The test facility of a 1/60-scale model for train-tunnel systems has been recently developed to investigate the effects of tunnel portal shapes, hood shapes and air-shafts for reducing the micro-pressure waves radiating towards the surroundings from the tunnel exit. The present test rig has been advanced from a 1/70-scale facility at NLR in Netherlands. The NLR test rig has the two-wise guidance system that needs two ears attached on the external surface of a model train nose. Therefore, their train models have irregular nose shapes. The main characteristics of the present facility are that the train model is guided by only one wire from the compressed air launcher to the absorber parts of test facility and the wire guidance hole is located at the axial center of a train model. In the present test rig, after a train model is launched, the air jet from the launcher does not enter the tunnel model. Experimental results were compared with numerical predictions to prove the performance of the test facility.

압밀시험의 수치해석에 의한 MCC 모델과 SSC 모델 비교 (Comparison of MCC and SSC Models Based on Numerical Analysis of Consolidation Test)

  • 권병해;임성훈
    • 한국농공학회논문집
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    • 제66권2호
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    • pp.1-12
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    • 2024
  • In order to integrate two consolidation theories of Terzaghi's consolidation theory and Mesri's secondary compression theory and to identify a model suitable for analyzing stress-strain behavior over time, numerical analysis on consolidation tests were conducted using a modified cam-clay model and a soft soil creep model and the following conclusions were obtained. The results of numerical analysis applying the theory that a linear proportional relationship is established between the void ratio at logarithmic scale and the permeability coefficient at logarithmic scale is better agreement with the result of oedometer test than the results of applying constant hydraulic conductivity. The modified cam-clay model is a model that does not include secondary compression, but the slope of the normal consolidation line corresponding to the compression index of the standard consolidation test includes secondary compression, so the actual settlement curve over time is lower than the predicted value through numerical analysis. It always gets smaller. Other previous studies that applied Terzaghi's consolidation theory to consolidation test analysis showed the same results and were cross-confirmed. The soft soil creep model, which includes secondary compression in the theory, showed good agreement in all sections including secondary compression in the consolidation test results. It was judged appropriate to use a soft soil creep model when performing numerical analysis of soft clay ground.

A Study on the Design of an Efficient Audit Model in the Area of Information System Testing Activities

  • Kim, Hee Wan;Jung, Yong Gyu
    • International Journal of Advanced Culture Technology
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    • 제9권1호
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    • pp.210-217
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    • 2021
  • In the case of an agile-based project, it was inadequate to perform a comprehensive inspection and evaluation on the establishment and operation of an information system by performing audit only with the audit and inspection elements provided by the existing information system audit and inspection system. In particular, in the case of the test activity area, it was necessary to improve the test activity audit check items to comprehensively check the agile-based development process by applying the existing audit system. To this end, a test activity improvement check model of the agile methodology audit model was presented by applying the repetition concept, a characteristic of the agile methodology. In order to empirically verify the model of this study, a survey was conducted for auditors and designers/developers who have experience in performing agile-based projects and auditing information systems. As a result of the questionnaire on the integrated test and system test in the test stage, more than 70% of the respondents were found to be suitable. More than 80% of the respondents judged that it was appropriate as a result of the questionnaire on "improvement and regression test progress according to integrated test and system test results" and "integrated test and functional actions of components and subsystems".

정차상태 시험 결과를 이용한 차량동특성 해석 모델의 검증 (Validation of the vehicle dynamic model for the static vehicle testing)

  • 박길배;성재호
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 춘계학술대회 논문집
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    • pp.317-325
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    • 2011
  • Vehicle model validation for the static vehicle testing has been done by comparison of the simulation results and test results and the parameters of the vehicle model to be used in the simulation have been adjusted to reflect the measured behaviour. The vehicle model fort the simulation should be validated by suitable tests and/or practical experience. The static vehicle test used to validate the vehicle model are the weight measurement, the wheel offloading test, the bogie rotational resistance test and the sway test. Finally, the computer simulation model has been validated and using the validated vehicle model the acceptance of the vehicle safety of the resistance to flange climbing derailment at low speed can be examined.

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1/10 축소 철근콘크리트보의 휨 거동에관한 실험적 연구 (An Experimental Study on the Flexural Behavior of 1/10-Scale Reinforced Concrete Beams)

  • 이한선;장신혁;김상규
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1995년도 봄 학술발표회 논문집
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    • pp.325-330
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    • 1995
  • Three types of model concrete with different mix ratios for 1/10 scale reinforced concrete model were made and tested to find the best solution for the simulation of mechanical characteristics of prototype concrete. Scaled reinforcing materials in diameter(D1.8) having similar con-figuration and mechanical properties with commercial deformed bars(D19) were prepared for 1/10 scale model tests of reinforced concrete structures. Two types of model test using D1.8 model reinforcing bars and model concrete, monotonic simple beam test and cyclic cantilever beam test, were performed to ensure and check the similitude of bond behavior between 1/10 scale model and prototype. The test results showed that the flexural behavior of 1/10 scale models can be simulated with accuracy enough for practical use in monotonic and cyclic loading test.

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Testing Outliers in Nonlinear Regression

  • Kahng, Myung-Wook
    • Journal of the Korean Statistical Society
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    • 제24권2호
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    • pp.419-437
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    • 1995
  • Given the specific mean shift outlier model, several standard approaches to obtaining test statistic for outliers are discussed. Each of these is developed in detail for the nonlinear regression model, and each leads to an equivalent distribution. The geometric interpretations of the statistics and accuracy of linear approximation are also presented.

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조합회로에 대한 계층 구조적 테스트 패턴 생성 알고리즘의 비용 모델 (A Cost Model of Hierarchical Automatic Test Pattern Generation Algorithms for Combinational Logic Circuits)

  • Hyoung Bok Min
    • 전자공학회논문지A
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    • 제28A권12호
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    • pp.65-72
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    • 1991
  • A cost model of test generation is presented in this paper. The cost of flat gate-level and hierarchical modular level test generation for combinational logic circuits are modeled. The model shows that the cost of hierarchical test generation grows as GlogGunder some assuptions, while the cost of gate-level test generation grows $G^2<$/TEX>, where G is the number of gates in a circuit under test. The cost model derived in this paper is used to explain why some test generation techniques are faster and why hierarchical test generators should be faster than flat test generators on large circuits.

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축소모형 강관추진실험 경향 분석 (Analysis of pipe roof method test with a reduced-scale model)

  • 엄기영;정관동;이성혁;천정연;장희정;이종태
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2010년도 춘계학술대회 논문집
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    • pp.664-670
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    • 2010
  • The study on mechanical behavior of the structure at the site includes experimental method and numerical analysis method. Experimental method is categorized into true-scale test and laboratory model test. A laboratory model test is to monitor the failure mechanism with a model simulated similar with a real ground so as to identify the quantitative result, while a true-scale model test is the approach which enables to identify the potential problems that may occur with a simulated construction situation similar with a real site circumstance. Thus this study was intended to carry out the experimental test of non open-cut excavation by pipe roof method which is mostly common in domestic sites. as well as was aimed at identifying the ground behavior occurred during pipe penetration using laboratory model test. Appropriate reduced-scale model was selected, taking into account of domestic geological characteristics and operation characteristics of traditional and high-speed rail trains and the qualitative evaluation of displacement was carried out based on a certain ground loss volume depending on excavation after categorizing trackbed settlement pattern by depth of top soil.

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