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Kim, M.D.;Choi, S.H.;Hong, S.W.;Lee, C.W.
- Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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- 2002.11b
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- pp.725-730
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- 2002
This paper presents an efficient modeling method for open cracked beam structures. An equivalent bending spring model is introduced to represent the structural weakening effect in the presence of open cracks. The proposed method adopts the exact dynamic element method (EDEM) to avoid the difficulty and numerical errors in association with re-meshing the structure. The proposed method is rigorously compared with a commercial finite element code. Experiments are also performed to validate the proposed modeling method. Finally, a diagnostic scheme for open cracked beam structures is proposed and demonstrated through a numerical example.
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Hwang, Sun-Myumg
- The KIPS Transactions:PartD
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- v.16D no.3
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- pp.361-370
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- 2009
Recently, the most mobile application software developers are being faced by short developing time (fast time-to-market), various requirements and requirement changes. In order to overcome the environment, developer should support user friendly GUI and assure the quality from the early developing process using GUI test method. This paper proposes a test method and tool for mobile software GUI, which reduces test time and supports comfortable test environment by user oriented UI design. We implemented a tool based on test scenarios based image flow for high testing accuracy and test case reusability. And the results show the characteristics of the method compared to the existing tools.
https://doi.org/10.3745/KIPSTD.2009.16-D.3.361 인용 PDF KSCI

Kang, J.S.;Sohn, J.M.;Choe, W.J.;Lee, B.W.;Seo, J.M.
- Proceedings of the KIEE Conference
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- 1999.07a
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- pp.357-359
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- 1999
It is necessary for the optimum design of switching devices to calculate repulsion forces acting on the closed electric contacts flowing over-current, e.g. inrush current and overload currents. In this paper, the forces generated by currents and flux densities at the contact point when circuit breakers are in closed position are obtained by using 3D finite element method. According to the analysis, the optimum configuration of wipe springs and arc extinguishing chambers are newly designed and consequently type tests show satisfactory results.
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Lee, B.W.;Park, K.B.;Sim, J.;Oh, I.S.;Lim, S.W.;Kim, H.R.;Hyun, O.B.
- Proceedings of the KIEE Conference
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- 2007.07a
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- pp.102-103
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- 2007
In order to apply resistive superconducting fault current limiters into electric power systems, the urgent issues to be settled are as follows, such as initial installation price of SFCL, operation and maintenance cost due to ac loss of superconductor and the life of cryostat, and high voltage and high current problems. The ac loss and high cost of superconductor and cryostat system are main bottlenecks for real application. Furthermore in order to increase voltage and current ratings of SFCL, a lot of superconductor components should be connected in series and parallel which resulted in extreme high cost. Thus, in order to make practical SFCL, we designed novel hybrid SFCL which combines superconductor and conventional electric equipment including vacuum interrupter, power fuse and current limiting reactor. The main purpose of hybrid SFCL is to drastically reduce total usage of superconductor by adopting current commutation method by use of superconductor and high fast switch. Consequently, it was possible to get the satisfactory test results using this method, and further works for practical applications are in the process.
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