• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.1 s.118
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• pp.3-9
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• 2007

In this paper, a numerical case study is carried out on the hydroelastic vibration of rectangular plate with various fluid field. It is assumed that the tank wall is clamped along the plate edges. The VMM(virtual mass method) of Nastran is used for the simulation of fluid domain and calculating natural frequency of fluid-coupled structure. In this paper, natural frequencies are calculated and compared for rectangular plates with various fluid field such as infinite fluid and finite fluid, length change of finite fluid field and various fluid contacting conditions.

• Journal of Korea Society of Digital Industry and Information Management
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• v.4 no.1
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• pp.105-117
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• 2008

T Abstract This study investigates the influence of differential factors on learner satisfaction by field-independent learning style in e-learning. Most of data were collected from students. Participants were classified based on a learning style typology (field-independent/dependent) and, then, analyzed was the influence of key factors on learner satisfaction using multiple regression analysis. This study suggests that e-Learning service providers need to differentiate learners based on learning style in order to improve learner satisfaction. Specially, Field independent learners are more likely to be satisfied by the teacher's provide degree of joyful, degree of contents, degree of learning control pacing, ability of problem solving and consistency.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.02a
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• pp.15-18
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• 2003

HTS(High Temperature Superconductor) tapes have dependence on critical characteristics such as electric, magnetic field and temperature. In order to confirm these effects, we examined the current transport characteristics of HTS tapes. First, after being fed DC and AC, the dependence of HTS tapes of 10cm on external magnetic field was investigated. On centeral region of HTS tape, about 1cm, external magnetic field was applied. Second, after applying DC of 50A to HTS tapes, we applied time variable magnetic field about 100mT and investigated the quench characteristics. Finally, AC, which is about 10 times of I$_{c}$, was applied to HTS tapes and over current characteristics were investigated. The data acquired in this study will be used as a source for the study of HTS cable conductor which is supposed to carry on.n.

• Journal of Information Technology Applications and Management
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• v.19 no.4
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• pp.153-169
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• 2012

In the rapidly changing field of Management Information Systems, the definition and educational programs must be continually reevaluated and revised. A study was conducted to find a way to which the modeling principle is applied for redefining the identity of Management Information Systems as an independent academic field and to develop a plausible MIS curriculum based on the modeling principle. Previous researches on the MIS frameworks, knowledge and technology requirements for IS professionals, and standard MIS curriculums were reviewed thoroughly. For this study, the Kantian cognitive model was adopted as a basis of modeling principle. The result shows that modeling ability has been the core competence of IS people in the field of MIS. The applicability of a modeling principle is also verified in establishing the identity of MIS and developing a normative MIS curriculum. For the MIS field to thrive as an independent academic field and research discipline, it is believed to be imperative for the discipline to have a unique educational goals distinguished from both other management areas, and sub-fields of computer science.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.943-945
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• 2000

In this paper described that study on the distribution and characteristics of axial magnetic field by mathematical analysis and experiment for axial magnetic field type vacuum interrupter that important part on vacuum circuit breaker. And, it was shown that inspected results of arc shape at breaking the current by typical axial magnetic field type model and new axial magnetic field type model.

• Journal of Industrial Technology
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• v.18
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• pp.131-138
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• 1998

Numerical modeling for electromagnetic exploration methods are essential to understand behaviours of electromagnetic fields in complex subsurfaces. In this study, a finite element method was adopted as a numerical scheme for the 2.5-dimensional forward problem. And a finite element equation considering linear conductivity variation was proposed when 2.5-dimensional differential equation to couple eletric and magnetic field was implemented. Model parameters were investigated for near-field with large source effects and far-field with responses dominantly by homogeneous half-space. Numerical responses by this study were compared with analytic solutions in homogeneous half-space and compared with other three dimensional numerical results.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1027-1028
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• 2007

In this paper, the variation of air-gap field intensity caused by the slot-opening in interior permanent magnet (IPM) motor is investigated, which is for predicting the instantaneous magnetic field more preciously in analytical method further. It is different with the approach of dealing the slot-opening effect on the air-gap field distribution with the "relative permeance" function in surface permanent magnet (SPM) motor. The prediction of the air-gap field in IPM motor is much more complex than SPM motor. In this study, an approximate estimation method is adopted based on analyzing the changing of flux path in both the IPM rotor part and stator part, and in additional an analytical function defined as "relative pole-arc" is built. The finite element method(FEM) is used for confirming the slot-opening effect on the field prediction.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.45.2-45.2
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• 2018

Twisted magnetic flux tubes (also called magnetic flux ropes) are believed to play a crucial role in solar eruptive phenomena. The evolution of a single flux rope with or without the influence of an overlying field of a simple geometry has been extensively studied and its physics is rather well understood. Observations show that interacting flux tubes are often involved in solar eruptions. It was Lau and Finn (1996) who intensively studied the interaction between two flux ropes, whose footpoints are anchored in two parallel planes. In this too simplified setting, the curvature of the flux rope axial fields is totally ignored. In our study, the footpoints of flux ropes are placed in a single plane containing a polarity inversion line as in the real solar active region. Our simulation study is performed for four cases: (1) co-axial field and co-axial current (co-helicity), (2) counter-axial field and co-axial current (counter-helicity), (3) co-axial field and counter-axial current (counter-helicity), and (4) counter-axial field and counter-axial current (co-helicity). Except case 3, each case is found to be related with certain eruptive features.

• Journal of the Korean Society for Precision Engineering
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• v.11 no.4
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• pp.47-57
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• 1994

This study investigates the crack propagation behavior to examine the effect of welding residual stress by the superposition method. Especially, as the crack propagation behavior is affected by the applied stress and the stress ratio in compressive residual stress filed, it is studied for three cases as follows; (1) $K_{min}$is smaller than l $K_{r}$l, (2) $K_{min}$ is smaller than l $K_{r}$l in the later stage, (3) $K_{min}$is lager than l $K_{r}$l. The resuslts show that the superposition method is very useful in all the three cases of compressive residual stress field, but is inappropriate in predicting the crack propagation behavior in tensile residual stress field.field.field.

• Journal of Radiation Industry
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• v.17 no.4
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• pp.405-409
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• 2023

The magnetic resonance imaging method is a technology that can diagnose patients using local magnetic field through local magnetic field through local magnetic field through local magnetic field and STEAM method using local magnetic field Currently, many diseases can diagnose many diseases using self-resonance methods. The purpose of this study is to provide optimal information about using magnetic resonance imaging method according to patients.In many studies, self-resonance imaging showed that self-resonance methods can effectively inspect brain cancer and liver diseases. mong them, this study, brain tumor tests, cervical cancer tests based on literature, there were effective parts of these four diseases, but it was clearly found that they should not use in clinical trials, but it is clearly found to improve and improve and improve. Therefore, it is believed that it will be based on the future studies.