• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.3
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• pp.73-81
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• 1998

In this paper, the necessity of developing effective nondestructive testing and monitoring techniques for the evaluation of structural integrity and performance is described. The evaluation of structural integrity and performance is especially important when the structures and subject to abrupt external forces such as earthquake. A prompt and extensive inspection is required over a large area of earthquake-damaged zone. This evaluation process is regarded as a part of performance-based design. In the paper, nondestructive testing and monitoring techniques particularly for concrete structures are presented as methods for the evaluation of structural integrity and performance. The concept of performance-based design is first defined in the paper followed by the role of evaluation of structures in the context of overall performance=based design concept. Among possible techniques for the evaluation, nondestructive testing methods for concrete structures using radar and a concept of using fiber sensor for continuous monitoring of structures are presented.

• Communications for Statistical Applications and Methods
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• v.8 no.3
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• pp.787-795
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• 2001

In this paper, Bayesian hypothesis testing procedures are proposed under the non-informative prior distributions, which can be thought as the Bayesian counterparts of the classical ones in the sense of using the concept of significance level. The performances of proposed procedures are compared with those of classical procedures through several examples.

• Archives of design research
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• v.14 no.3
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• pp.69-76
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• 2001

In the new product development process, concept testing which screens ideas with the highest probability of market success is very effective in predicting the success of a new product. However, designers do not have accurate guidelines in new product development because the structure of cause and effect of consumers' preference - the most important part of concept testing - has not been provided as quantitative data. Therefore, the aim of this study is to present guidelines for new product concept development through applying means-end chain theory and product form theory which explains what kinds of benefits cause consumers to purchase a product and what kinds of design attributes meet the benefits. In this study, after reviewing means-end chain theory and product form theory, and developing a research model, guidelines for a concept product development (TV are provided through an empirical study.

• Journal of Information Processing Systems
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• v.6 no.2
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• pp.197-208
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• 2010

Test scenarios can be derived based on some system models for requirements validation purposes. Model-based test suite reduction aims to provide a smaller set of test scenarios which can preserve the original test coverage with respect to some testing criteria. We are proposing to apply Formal Concept Analysis (FCA) in analyzing the association between a set of test scenarios and a set of transitions specified in a state machine model. By utilizing the properties of concept lattice, we are able to determine incrementally a minimal set of test scenarios with adequate test coverage.

• Journal of the Korean Society for Nondestructive Testing
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• v.10 no.2
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• pp.38-42
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• 1990

The specific strength of the fiber reinforced composite material is closely related to the anisotropy of the material. For the quantitative characterization of the anisotropy in the composite material, applied was CODF concept which was extensively used in the metallic material. As the results, the anisotropy of the material could be quantitatively analysed from the measurement of the phase velocities of the angular dependent $SH_o$ waves.

• Journal of The Korean Association For Science Education
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• v.17 no.3
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• pp.333-343
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• 1997

The purpose of the present study was to investigate an appropriate instructional model in order to remedy students' misconception. As hypotheses of this study, three instructional models, cognitive conflicting, hypothesis testing, and learning cycle models, on biological 'osmosis' concept were tested in 176 high school students. Results of the present study are as follows: 1. All groups used one of three instructional models showed a statistically significant improvement in conceptual change on the 'osmosis' concept between before and after the instruction. In addition, the three hypothesized instructional models were more effective in conceptual change than a traditional expository instruction. 2. There was a statistically significant difference among three experimental groups. Cognitive conflicting model and hypothesis testing model was more effective than learning cycle models. 3. An interviewing after instruction showed that students who had scientific concept on the 'osmosis' through the instruction could effectively apply the concept to other context more than students who had no scientific concept through instruction. The present study indicated that instructional model play an important role on students' conceptual change in science classroom. According to the result of this study, the instruction emphasizing students' active participation in class and scientific reasoning process is more appropriate to remedy misconception that the instruction using students' passive participation in class and expository teaching procedure. This study also indicated that students' concept acquired through instruction is one of important factors to apply it to other context.

• International Journal of Reliability and Applications
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• v.2 no.4
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• pp.263-268
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• 2001

Shanmugam(1991) generalized the Poisson distribution to capture a restriction on the incidence rate $\theta$ (i.e. $\theta$ ＜ $\beta$, an unknown upper limit), and named it incidence rate restricted Poisson (IRRP) distribution. Using Neyman's C($\alpha$) concept, Shanmugam then devised a hypothesis testing procedure for $\beta$ when $\theta$ remains unknown nuisance parameter. Shanmugam's C ($\alpha$) based .results involve inverse moments which are not easy tools, This article presents an alternate testing procedure based on likelihood ratio concept. It turns out that likelihood ratio test statistic offers more power than the C($\alpha$) test statistic. Numerical examples are included.

• Proceedings of the KIEE Conference
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• 2002.04a
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• pp.64-67
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• 2002

To increase the short-circuit testing capacity of distribution transformers, testing facility has been installed for KEPCO in Vi-wang. The power supply of testing facility is directly supplied from the network substation located closely. Testing can be performed up to 300 kVA for single-phase transformers, 500 kVA for three-phase transformers. Operating with this facility, the distribution company is able to maintain the reliable supply of electricity. Also the critical quality of transformers from manufacturers can be verified by short-circuit testing. This paper describes the design concept and specification of newly developed equipment and the procedure of short-circuit test.

• 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.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.7
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• pp.135-143
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• 2014

Electrified vehicles can be classified with hybrid electric vehicles, battery electric vehicles and fuel cell electric vehicles. These vehicles have two more than energy converters which are the part of a powertrain. It is particularly difficult to estimate the power of hybrid electric vehicles due to two different energy converters with different power characteristics. Therefore, a new power concept for these vehicles is needed. The vehicle power as the new concept for solving this problem was defined in this study. The test method and the procedure were made a development in this study. Four electrified vehicles with different electric fraction were used to validate the method. Two percentage of COV was suggested as a criterion for the maximum vehicles power based on the previous studies. The repeatability of this method was within ${\pm}2$ per cent for the maximum vehicle power and within ${\pm}5$ per cent for the vehicle speed at maximum vehicle power.