• Title/Summary/Keyword: Testing methods

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Effects of the Teaching and Learning Programs for Science Teachers' Scientific Hypothesis Testing-method Invention (과학교사를 위한 가설검증방법 고안 교수-학습 프로그램의 효과)

  • Jeong, Jin-Su
    • Journal of The Korean Association For Science Education
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    • v.28 no.6
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    • pp.664-674
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    • 2008
  • The purpose of this study was to analyze the effects of the teaching and learning programs for science teachers' scientific hypothesis testing-method invention. Subjects were 30 secondary school science teachers. The potato juice task was administered to the subjects before and after instructional treatments. The four-step strategy including the steps of identifying factors, identifying variables, selecting variables and inventing methods, was applied to the development of the teaching and learning programs for the science teachers. The programs were developed by 6 experts through the R&D method. The results of this study revealed that the number and elaborateness of science teachers' scientific hypothesis testing-methods increased after the instructional treatments. The testing ability of testing-methods invented by science teachers in the posttest was stronger than the one of the methods invented in the pretest. This study also discussed the implications of these findings for teaching and learning in science education.

Current Uses and Research Activity Regarding Non-testing Methods Including (Q)SARs in Various Chemical Regulatory Programs (국외 화학물질 관리 제도 내에서의 (Q)SARs 및 비-시험 방법 사용과 관련 연구 현황)

  • Ha, Mi-Hee;Kim, Sang-Hun
    • Environmental Analysis Health and Toxicology
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    • v.24 no.3
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    • pp.261-270
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    • 2009
  • To make measurable regulatory decisions of chemicals, it is necessary to consider their effect on the human health and ecosystem. In principle, this is based on relevant toxicity studies conducted by accepted guidelines. However, current regulatory programs in various countries confront challenges related to risk assessment of large numbers of chemicals within the restricted resources and time. Therefore there is a need for more efficient approach to limit the number of tests to be conducted. This promotes the development of powerful nontesting methods (e.g. (Q)SARs) and permits to use the predicted data for regulatory purpose. In this article, current status of non-testing methods in various chemical regulatory programs was reviewed in terms of their application and research activity on them. Finally, their usefulness associated with development of domestic regulatory program was suggested.

Effect of horizontal at rest pressure (Po) on elastic modulus from pressuremeter testing

  • Alzubaidi, Radhi M.
    • Geomechanics and Engineering
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    • v.17 no.3
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    • pp.247-252
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    • 2019
  • Modulus of deformation of soil is an essential parameter used for design analysis of foundations, despite its importance; little attention is paid to developing empirical models for predicting the sensitivity of deformation moduli to other parameters that obtained from the pressuremeter tests. Various methods of analysis used to predict the horizontal at rest pressure from pressuremeter testing ($P_o$), these values showed distinctive variations, five methods used to evaluate the values of horizontal at rest pressure, these values been used to evaluate the modulus of elasticity using three methods of analysis. The values of modulus showed distinctive increase when the values of horizontal at rest pressure increase for the same pressuremeter test, these increases may reach to 65%. This sensitivity of the moduli to values of horizontal lead the author to propose some reliable methods of analysis for both the horizontal at rest pressure and the modulus of deformation from pressuremeter testing.

Development of devices and methods for simulation of hurricane winds in a full-scale testing facility

  • Huang, Peng;Chowdhury, Arindam Gan;Bitsuamlak, Girma;Liu, Roy
    • Wind and Structures
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    • v.12 no.2
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    • pp.151-177
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    • 2009
  • The International Hurricane Research Center (IHRC) at Florida International University (FIU) is pursuing research to better understand hurricane-induced effects on residential buildings and other structures through full-scale aerodynamic and destructive testing. The full-scale 6-fan Wall of Wind (WoW) testing apparatus, measuring 4.9 m tall by 7.3 m wide, is capable of generating hurricane-force winds. To achieve windstorm simulation capabilities it is necessary to reproduce mean and turbulence characteristics of hurricane wind flows. Without devices and methods developed to achieve target wind flows, the full-scale WoW simulations were found to be unsatisfactory. To develop such devices and methods efficiently, a small-scale (1:8) model of the WoW was built, for which simulation devices were easier and faster to install and change, and running costs were greatly reduced. The application of such devices, and the use of quasiperiodic fluctuating waveforms to run the WoW fan engines, were found to greatly influence and improve the turbulence characteristics of the 1:8 scale WoW flow. Reasonable reproductions of wind flows with specified characteristics were then achieved by applying to the full-scale WoW the devices and methods found to be effective for the 1:8 scale WoW model.

Testing Environment based on TTCN-3 for Network-based Embedded Software (TTCN-3를 이용한 네트워크 기반 임베디드 소프트웨어 테스팅 환경 구축)

  • Chae, Hochang;Jin, Xiulin;Cho, Jeonghun;Lee, Seonghun
    • IEMEK Journal of Embedded Systems and Applications
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    • v.5 no.1
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    • pp.29-38
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    • 2010
  • It is highly requested that the more complicated embedded software is used for high performance and multiple functions of the systems. This is inevitably increasing the errors. Therefore the embedded software testing is getting important recently. There are not general testing methods which are able to be applied for any embedded systems, but via this research, we introduce a testing method which is based on TTCN-3, a testing standard, for embedded systems. A testing environment for network-based embedded software is implemented with considering the features of TTCN-3 testing which is based on message exchange. The testing environment has two additional parts with TTCN-3 test system, the network analyzer to access the network-based systems and the communication interface which is suggested for embedded systems in previous work, and we have implemented the whole testing environment with interacting these two parts. In addition to the normal testing domain, called single node testing as a unit testing of V-model, we suggest another concept to test multiple nodes in network. It could be achieved by adding keywords such as supervisor and object which are describing the feature of TTCN-3 testing component and generating the TTCN-3 Executable code which contains new keywords. The testing has done for embedded software which is based on CAN network and the demonstration of the testing environment has been shown in this paper.

Testing Procedure for Scale Shift at an Unknown Time Point

  • Song, Il-Seong
    • Communications for Statistical Applications and Methods
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    • v.3 no.1
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    • pp.21-27
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    • 1996
  • A testing procedure is considered to the problem of testing whether there exists a shift in scale at an unknown time point whem a fixed number of observations are drawn successively in time. A test statistic based on squared ranks test for equal variances is suggested and its aymptotic distrbution is dereived. Small sample power comparisons are performed.

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Testing for Grouped Heteroscedasticity in Linear Regression Model

  • Song, Seuck Heun;Choi, Moon Kyung
    • Communications for Statistical Applications and Methods
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    • v.11 no.3
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    • pp.475-484
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    • 2004
  • This paper consider the testing problem of grouped heteroscedasticity in the linear regression model. We provide the Lagrange Multiplier(LM), Wald, Likelihood Ratio (LR) test statistis for testing of grouped heteroscedasticity. Monte Carlo experiments are conducted to study the performance of these tests.

Comparison of Major Black-Box Testing Methods in Object-Oriented Software (객체지향 소프트웨어를 위한 주요 블랙박스 테스트 기법들의 비고)

  • Seo, Kwang-Ik;Choi, Eun-Man
    • Journal of KIISE:Software and Applications
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    • v.33 no.1
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    • pp.1-16
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    • 2006
  • As the size of software is getting huge, it has been impossible for testers to test all of source coed. Therefore, the method which uses information of requirements for testing has been researched and accepted. Although there are a lot of test methods based on requirement specification, each method has a different approach and coverage. So we should consider their various approach and coverage in the stage of test planning. This paper presents the empirical comparison and the result by applying various black-box testing methods to software system. For this experiment we studied five black-box testing methods including UML based specification technique. We applied the five testing methods to application system and evaluated the coverage of extracted test case.

Non-destructive Testing Methods to Evaluate the Effectiveness of Crack Repair Using Expoxy and Microcement (균열 주입부의 비파괴 검사에 의한 주입효과 판정에 관한 연구)

  • 최홍식;이시우;이호범;송영철;방기성
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.05a
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    • pp.841-846
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    • 2002
  • Development on non-destructive testing methods were performed to evaluate the effectiveness of crack repair for test beams induced a crack. Cracked beams are repaired with expoxy and microcement, and then they are tested by two methods, the ultrasonic pulse velocity method and the transfer function method. It is proved that the ultrasonic pulse velocity method is very valid for the evaluation of the effectiveness on expoxy repair, and the transfer function method is very applicable to evaluate the effectiveness on microcement repair.

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Nonparametric Inference for Accelerated Life Testing (가속화 수명 실험에서의 비모수적 추론)

  • Kim Tai Kyoo
    • Journal of Korean Society for Quality Management
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    • v.32 no.4
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    • pp.242-251
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    • 2004
  • Several statistical methods are introduced 1=o analyze the accelerated failure time data. Most frequently used method is the log-linear approach with parametric assumption. Since the accelerated failure time experiments are exposed to many environmental restrictions, parametric log-linear relationship might not be working properly to analyze the resulting data. The models proposed by Buckley and James(1979) and Stute(1993) could be useful in the situation where parametric log-linear method could not be applicable. Those methods are introduced in accelerated experimental situation under the thermal acceleration and discussed through an illustrated example.