• Title/Summary/Keyword: evaluation experiments

Search Result 2,802, Processing Time 0.03 seconds

Seismic Stability and Fatigue Performance Test of Lead Rubber Bearings (납-적층고무받침의 지진안정성 및 피로거동 실험)

  • Cho, Chang-Beck;Kwahk, Im-Jong;Kim, Young-Jin;Kwark, Jong-Won;Cho, Hae-Jin
    • Proceedings of the Earthquake Engineering Society of Korea Conference
    • /
    • 2006.03a
    • /
    • pp.537-544
    • /
    • 2006
  • In this study, performance level evaluation tests have been actually performed on laminated rubber seismic isolation bearings (LRB) made in Korea. To provide basic data for setting up fabrication criteria and performance evaluation criteria three real scale LRB were tested and the test results were analysised. Accordingly, a large capacity test device has been designed and manufactured to implement the tests. The device selected for evaluation is a circular LRB actually applied in bridges. Evaluation tests were conducted using full-scale LRB with diameter of 851mm in the rubber part and total height of 215mm of which the effective horizontal stiffness and equivalent damping ratio have been measured during the experiments.

  • PDF

An Investigation on the Assessment Tool and Status of Assessment in the 'Scientific Inquiry Experiment' of the 2015 Revised Curriculum (2015 개정 교육과정 '과학탐구실험' 평가 도구 및 평가 현황 탐색)

  • Baek, Jongho;Byun, Taejin;Lee, Dongwon;Shim, Hyeon-Pyo
    • Journal of The Korean Association For Science Education
    • /
    • v.40 no.5
    • /
    • pp.515-529
    • /
    • 2020
  • 'Scientific inquiry experiments', which was newly created subjects in the 2015 revised curriculum, was expected in the aspect of learning science and developing core competences through science practices. Based on changed view of evaluation, assessments of a practice-centered subject 'Scientific inquiry experiments' should be try to conducted in various ways, but many challenges were reported. In this study, through analysis of current status of assessment of the subject, we intended to find the way of conducting and supporting 'Scientific inquiry experiments'. We collected assessment materials and explanatory description about them from 25 teachers who taught 'Scientific inquiry experiments' in 2018 and 2019. And we analyzed the cases with framework which were consisted with three main categories: elements, standards, methods of assessments. Also, we investigated how the results of assessment were utilized. For the validity, we requested verification of the results of our data analysis to experts of science education and science teachers. From them, we also collected their opinions about our analysis. As a result of the study, teachers assessed some elements of inquiry skills such as 'analysis and interpreting the data', 'conducting inquiry' more than others which were closely related to what subject-matter the teachers used to organized inquiry program with. In the aspect of domain of assessments, though cognitive domain and affective domain as well as skills were evaluated, we also found that the assessment of those domains had some limitation. In terms of standard of assessment, the goals of assessment were presented in most cases, but there were relatively few cases which had the specific criteria and the stepwise statements of expected performance of students. The time and subject of the assessment were mainly post-class and teachers, and others such as in-class assessments, peer-assessments were used only in specific contexts. In all cases, the results of assessments used for calculating students' grade, but in some cases, we could observe that the results used for improving teaching and feedback for students. Based on these results, we discussed how to support the assessments of 'Scientific inquiry experiments'.

Interactive Roles of Local versus Global Primed Identity and Advertisement Framing on Brand Evaluation (브랜드평가에 대한 아이덴티티의 점화와 광고프레임의 상호작용효과)

  • Choi, Nak Hwan;Liu, Cong
    • Science of Emotion and Sensibility
    • /
    • v.16 no.1
    • /
    • pp.11-28
    • /
    • 2013
  • This article aims to explore the interactive roles of types of primed identity (local versus global identity) and types of ad framing on brand evaluations. The authors designed 2 experiments in which each experiment followed a $2{\times}2$ between-subject design. The empirical results showed that a gain-framed ad induced more positive emotional responses than a loss-framed ad, and the positive affective responses lead to more favorable brand evaluation. Furthermore, the results showed that there were interactive effects of primed identity and types of advertisement frame on brand evaluation. In the additional analysis, the results showed that when people with local identity were exposed to the gain-framed ad, they would engage in a higher level of integration processing than those in the control group, which in turn induced more favorable evaluation to the local brand. That is, the integration processing mode played a mediating role between the interaction (local id priming ${\times}$ ad frame) and the local brand evaluation. However, in the case of global brand evaluation, the integration processing mode did not play such a mediating role.

  • PDF

Experimentally Evaluation of a Liquid Pool Spreading Model with Continuous Release (연속누출을 가지는 액체 풀 확산 모델의 실험적 평가)

  • KIM, TAEHOON;DO, KYU HYUNG;KIM, MYUNGBAE;HAN, YONG-SHIK;CHOI, BYUNG-IL
    • Journal of Hydrogen and New Energy
    • /
    • v.26 no.6
    • /
    • pp.659-665
    • /
    • 2015
  • In this study, an experimental investigation is performed for evaluation of a liquid pool spreading model with continuous release. The model considered in this study was developed based on a concept which means that the liquid pool spreading is governed by a balance between an inertia force from gravity and a frictional force from friction with the ground under the whole base of the liquid pool. For evaluation of the model, experimental study is performed. Experimental apparatus is setup for measuring release rate, spreading velocity, and evaporation rate from a liquid pool. The experimental results are compared with results from the model. By applying release and evaporation rates obtained from experiments to solving the model, liquid pool radius variation according to time can be obtained. For evaluation of an effect of friction force in the spreading model, results obtained from the models with and without the friction force are compared with those obtained from the experiments. As a result, it is shown that there exists a large deviation between the results obtained from the model without the friction force and the experimental results. On the other hand, the tendency of liquid pool radius variation according to time is similar between the results obtained from the model without the friction force and the experimental results.

Sensitivity Evaluation and Approximate Optimization Analysis for Structure Design of Module Hull Type Trimaran Pontoon Boat (모듈 선체형 삼동 폰툰 보트의 구조설계 민감도 평가와 근사 최적화 해석)

  • Bo-Youp Choi;Chang-Ryeon Son;Joon-Sik Son;Min-Ho Park;Chang-Yong Song
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.26 no.6_3
    • /
    • pp.1279-1288
    • /
    • 2023
  • Recently, domestic leisure boats have been actively researching eco-friendly product development to enter the global market. Since the hulls of existing leisure boats are mainly made of fiber reinforced plastic (FRP) or aluminum, design techniques for securing structural safety by applying related materials have been mainly studied. In this study, an initial structural design safety assessment of a trimaran pontoon leisure boat with a modular hull structure and eco-friendly high-density polyethylene (HDPE) material was conducted, and sensitivity evaluation and optimization analysis for lightweight design were performed. The initial structural design safety assessment was carried out by creating a finite element analysis model and applying the loading conditions specified in the ship classification regulation to check whether the specified allowable stresses are satisfied. For the sensitivity evaluation, the influence of stress and weight of each hull structural member was evaluated using the orthogonal array design of experiments method, and an approximate model based on the response surface method was generated using the results of the design of experiments. The optimization analysis set the thickness of the hull structural members as the design variable and considered the optimal design formulation to minimize the weight while satisfying the allowable stress. The algorithm of the optimization analysis applied the Gradient-population Based Optimizer (GBO) to improve the accuracy of the optimal solution convergence while reducing the numerical cost. Through this study, the optimal design of a newly developed eco-friendly trimaran pontoon leisure boat with a weight reduction of 10% was presented.

The Verification of TEXAS-V code for TROI Experimental Results and the Evaluation of the Ex-vessel Steam Explosion Load (TROI 실험결과를 활용한 TEXAS-V 코드 검증 및 원자로 노외증기폭발 하중평가)

  • Park, Ik-Kyu;Kim, Jong-Hwan;Min, Beong-Tae;Hong, Seong-Ho;Kim, Hee-Dong;Hong, Seong-Wan
    • Proceedings of the KSME Conference
    • /
    • 2007.05b
    • /
    • pp.3485-3490
    • /
    • 2007
  • The TEXAS-V code tuned for TROI-13 was used for analyzing the parametric findings in TROI experiments. The calculations on the melt composition are relatively similar to the TROI experimental results. The water depth effect in TEXAS-V code seems to be consistent with TROI experiments in some degree. The water area effect of TEXAS-V calculations seems not to be harmonious to that in TROI experiments. This seems to indicate that TEXAS-V as 1-dimensional code or as the numerical steam explosion has a limitation on estimating area effect. Thus, TEXAS-V tuned for TROI-13 seems to have an ability to estimate the parametric effect of TROI experiments. The evaluated TEXAS-V was used for estimating the ex-vessel steam explosion load. The calculated explosion pressure and load were about 40 MPa and 75 kPa.sec, which are not much threatening level for containment integrity, but are arguable value for the integrity.

  • PDF

An efficient Reliability Analysis Method Based on The Design of Experiments Augmented by The Response Surface Method (실험계획법과 반응표면법을 이용한 효율적인 신뢰도 기법의 개발)

  • 이상훈;곽병만
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2004.10a
    • /
    • pp.700-703
    • /
    • 2004
  • A reliability analysis and design procedure based on the design of experiment (DOE) is combined with the response surface method (RSM) for numerical efficiency. The procedure established is based on a 3$^n$ full factorial DOE for numerical quadrature using explicit formula of optimum levels and weights derived for general distributions. The full factorial moment method (FFMM) shows good performance in terms of accuracy and ability to treat non-normally distributed random variables. But, the FFMM becomes very inefficient because the number of function evaluation required increases exponentially as the number of random variables considered increases. To enhance the efficiency, the response surface moment method (RSMM) is proposed. In RSMM, experiments only with high probability are conducted and the rest of data are complemented by a quadratic response surface approximation without mixed terms. The response surface is updated by conducting experiments one by one until the value of failure probability is converged. It is calculated using the Pearson system and the four statistical moments obtained from the experimental data. A measure for checking the relative importance of an experimental point is proposed and named as influence index. During the update of response surface, mixed terms can be added into the formulation.

  • PDF

An Evaluation of the Ex-vessel Steam Explosion Load Against TROI Experimental Results (TROI 실험결과를 활용한 원자력발전소 중대사고시 노외 증기폭발 하중평가)

  • Park, Ik-Kyu;Kim, Jong-Hwan;Min, Beong-Tae
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.33 no.8
    • /
    • pp.622-628
    • /
    • 2009
  • The TEXAS-V code tuned for TROI-13 was used for analyzing the parametric findings in TROI experiments. The calculations on the melt composition are relatively similar to the TROI experimental results. The water depth effect in TEXAS-V code seems to be consistent with TROI experiments in some degree. The water area effect of TEXAS-V calculations seems not to be harmonious to that in TROI experiments. This seems to indicate that TEXAS-V as 1-dimensional code or as the numerical steam explosion has a limitation on estimating area effect. Thus, TEXAS-V tuned for TROI-13 seems to have an ability to estimate the parametric effect of TROI experiments. The evaluated TEXAS-V was used for estimating the ex-vessel steam explosion load. The calculated explosion pressure and load were about 40 MPa and 75 kPa.sec, which are not much threatening level for containment integrity.

Development and Application of Science Report Performance Evaluation System Based on the Web (웹을 기반으로 한 과학 보고서 수행 평가 시스템 개발 및 적용)

  • Kim, Jin-Ha;Goh, Byung-Oh
    • Journal of The Korean Association of Information Education
    • /
    • v.12 no.1
    • /
    • pp.41-48
    • /
    • 2008
  • Current performance evaluation of the natural science section mainly focuses on teacher evaluation, which causes slow feedback on the evaluation result and little evaluation on colleagues due to limits of time and space. In addition, report performance evaluation, which is a main target of the evaluation in the natural science section, is conducted mostly based on records of experiments and observation without any systematic forms. Such performance evaluation cannot meet expectation on the evaluation for a self-adjustment through instant feedback on the evaluation result and improvement of motivation through sharing common performance standard. Therefore, the study here completes an experiment/research report through information sharing and discussion among colleague learners based on the web and uses it for colleague or teacher evaluation. In addition, it is intended to recognize needs of learners and develop a performance evaluation system that can provide learners with appropriate feedback through the result.

  • PDF

Depth Evaluation from Pattern Projection Optimized for Automated Electronics Assembling Robots

  • Park, Jong-Rul;Cho, Jun Dong
    • IEIE Transactions on Smart Processing and Computing
    • /
    • v.3 no.4
    • /
    • pp.195-204
    • /
    • 2014
  • This paper presents the depth evaluation for object detection by automated assembling robots. Pattern distortion analysis from a structured light system identifies an object with the greatest depth from its background. An automated assembling robot should prior select and pick an object with the greatest depth to reduce the physical harm during the picking action of the robot arm. Object detection is then combined with a depth evaluation to provide contour, showing the edges of an object with the greatest depth. The contour provides shape information to an automated assembling robot, which equips the laser based proxy sensor, for picking up and placing an object in the intended place. The depth evaluation process using structured light for an automated electronics assembling robot is accelerated for an image frame to be used for computation using the simplest experimental set, which consists of a single camera and projector. The experiments for the depth evaluation process required 31 ms to 32 ms, which were optimized for the robot vision system that equips a 30-frames-per-second camera.