• KIPS Transactions on Software and Data Engineering
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• v.11 no.4
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• pp.179-188
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• 2022

There have been many successful researches on a bearing fault diagnosis based on Deep Learning, but there is still a critical issue of the data distribution difference between training data and test data from their different working conditions causing performance degradation in applying those methods to the machines in the field. As a solution, a data adaptation method has been proposed and showed a good result, but each and every approach is strictly limited to a specific applying scenario or presupposition, which makes it still difficult to be used as a real-world application. Therefore, in this study, we have proposed a method that, using a data transformation with MFCCs and a simple CNN architecture, can perform a robust diagnosis on a target domain data without an additional learning or tuning on the model generated from a source domain data and conducted an experiment and analysis on the proposed method with the CWRU bearing dataset, which is one of the representative datasests for bearing fault diagnosis. The experimental results showed that our method achieved an equal performance to those of transfer learning based methods and a better performance by at least 15% compared to that of an input transformation based baseline method.

• Smart Structures and Systems
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• v.31 no.3
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• pp.283-299
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• 2023

Structural stability of floating platforms has long since been a crucial issue in the field of marine engineering. Excessive motions would not only deteriorate the operating conditions but also seriously impact the safety, service life, and production efficiency. In recent decades, several control devices have been proposed to reduce unwanted motions, and an attractive one is the tuned heave plate (THP). However, the THP system may reduce or even lose its effectiveness when it is mistuned due to the shift of dominant wave frequency. In the present study, a novel adaptive tuned heave plate (ATHP) is proposed based on inerter by adjusting its inertance, which allows to overcome the limitation of the conventional THP and realize adaptations to the dominant wave frequencies in real time. Specifically, the analytical model of a representative semisubmersible platform (SSP) equipped with an ATHP is created, and the equations of motion are formulated accordingly. Two optimization strategies (i.e., J₁ and J₂ optimizations) are developed to determine the optimum design parameters of ATHP. The control effectiveness of the optimized ATHP is then examined in the frequency domain by comparing to those without control and controlled by the conventional THP. Moreover, parametric analyses are systematically performed to evaluate the influences of the pre-specified frequency ratio, damping ratio, heave plate sizes, peak periods and wave heights on the performance of ATHP. Furthermore, a Simulink model is also developed to examine the control performance of ATHP in the time domain. It is demonstrated that the proposed ATHP could adaptively adjust the optimum inertance-to-mass ratio by tracking the dominant wave frequencies in real time, and the proposed system shows better control performance than the conventional THP.

• Earthquakes and Structures
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• v.8 no.2
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• pp.379-399
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• 2015

Existing building structures can easily present material mechanical properties which can largely vary even within a single structure. The current European Technical Code, Eurocode 8, does not provide specific instructions to account for high variability in mechanical properties. As a consequence of the high strength variability, at the occurrence of seismic events, the structure may evidence unexpected phenomena, like torsional effects, with larger experienced deformations and, in turn, with reduced seismic performance. This work is focused on the torsional effects related to the irregular stiffness and strength distribution due to the concrete strength variability. The analysis has been performed on a case-study, i.e., a 3D RC framed 4 storey building. A Normal distribution, compatible to a large available database, has been taken to represent the concrete strength domain. Different plan layouts, representative of realistic stiffness distributions, have been considered, and a statistical analysis has been performed on the induced torsional effects. The obtained results have been compared to the standard analysis as provided by Eurocode 8 for existing buildings, showing that the Eurocode 8 provisions, despite not allowing explicitly for material strength variability, are conservative as regards the estimation of structural demand.

• Korea-Australia Rheology Journal
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• v.11 no.3
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• pp.233-240
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• 1999

In order to understand the flow behavior of Electrorheological (ER) fluid, dynamic simulation has been intensively performed for the last decade. When the shear flow is applied, it is easy to carry out the simulation with relatively small number of particles because of the periodic boundary condition. For the squeezing flow, however, it is not easy to apply the periodic boundary condition, and the number of particles needs to be increased to simulate the ER system more realistically. For this reason, the simulation of ER fluid under squeezing flow has been mostly performed with some representative chains or with the approximation that severely restricts the flow geometry to reduce the computational load. In this study, Message Passing Interface (MPI), which is one of the most widely-used parallel processing techniques, has been employed in a dynamic simulation of ER fluid under squeezing flow. As the number of particles used in the simulation could be increased significantly, full domain between the electrodes has been covered. The numerical treatment or the approximation used to reduce the computational load has been evaluated for its validity, and was found to be quite effective. As the number of particles is increased, the fluctuation of the normal stress becomes diminished and the prediction in general was found to be qualitatively In good agreement with the experimental results.

• Journal of the Korean Society for information Management
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• v.32 no.3
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• pp.69-97
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• 2015

This study aims to analyse the research areas and trends of reading (reading instruction) abroad in the respect of LIS, and suggest future research tasks. First, I reviewed the controlled keywords in SU field of LISTA database and the entries of DDC 23, and identified the research areas of reading and reading instruction in overseas. Second, I analysed the research trends of this field by applying a intellectual structure analysis on 2,115 research articles (1914~2014) retrieved from a representative database in the areas of Library and Information Science (LISTA). Third, Based on the results of these analysis, I suggested the future research tasks of this field in the domain of library and information science.

• Cartoon and Animation Studies
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• s.11
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• pp.73-85
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• 2007

The purpose of this study is to analyze collage of animated film is able to build up total embodiment of thought. Surrealism Collage intend to combination of various characters including new attempts and pluralistic features. In particular, the fantastic, irrational characteristics of expression and extravagant and unfamiliar artistic technique of Surrealism Collage are actively introduced and explored as elements to make new image and suggest the possibility of another reality. This image has been connected Raoul Servais animation film called . The use of this film technique gives a touch that is sensibly different from the digital encrustation technique which justifies it. Representative animator of Surrealism Raoul Servais expands the domain of his own creative works by succeeding to Surrealistic movement.

• Structural Engineering and Mechanics
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• v.51 no.6
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• pp.923-937
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• 2014

The rational finite element method is different from the standard finite element method, which is constructed using basic solutions of the governing differential equations as interpolation functions in the elements. Therefore, it is superior to the isoparametric approach because of its obvious physical meaning and accuracy; it has successfully been applied to the isotropic elasticity problem. In this paper, the formulation of rational finite elements for plane orthotropic elasticity problems is deduced. This method is formulated directly in the physical domain with full consideration of the requirements of the patch test. Based on the number of element nodes and the interpolation functions, different approaches are applied with complete polynomial interpolation functions. Then, two special stiffness matrixes of elements with four and five nodes are deduced as a representative application. In addition, some typical numerical examples are considered to evaluate the performance of the elements. The numerical results demonstrate that the present method has a high level of accuracy and is an effective technique for solving plane orthotropic elasticity problems.

• Knowledge Management Research
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• v.10 no.2
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• pp.15-33
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• 2009

Telecommunications-broadcasting convergence in the domain of IT is a representative phenomenon that is expected to provide the saturated existing markets with a new source of profit. Especially, T-Commerce combines familiarity of TV and immediacy of the Internet which are expected to cover all the users familiar with each media and expand the existing commercial transactions. Telecommunications-broadcasting convergence in Korea, however, is focusing on technical and regulatory aspects so that research on the real users is not up to the mark yet. This is the most fundamental problem in hampering growth in the corresponding service and market. Thus, we are proposing an adoption model on T-Commerce to rapidly expand the convergence service through understanding the potential users. Perceived utilitarian and hedonic values, perceived interactivity, media substitution and personal innovativeness have been examined as the factors influencing the users' intention to adopt a new convergence service. As a result of empirical analysis, it is verified that perceived utilitarian and hedonic values and personal innovativeness directly influenced the users' intention to adopt whereas perceived interactivity had indirect affect on them. T-Commerce service providers should not only emphasize on the benefit that the older media could not provide the users with, but also provide them with more pleasure and entertaining experience during the course of satisfying the users' needs to distinguish T-Commerce from the other existing media.

• Journal of Ocean Engineering and Technology
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• v.24 no.1
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• pp.153-160
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• 2010

This paper deals with the topology optimized design of the riser support structures for floating production storage and offloading units (FPSOs) under global and local loading conditions. For a preliminary study and validation of the numerical approach, a simplified plate under static loading is first evaluated with the representative topology optimization methods, the Homogenization Design Method (HDM) and Density Method (DM) or Simple Isotropic Material with Penalization (SIMP). In the context of the corresponding riser support structures, the design problem is formulated such that structure shapes based on design domain variables are determined by minimizing the compliance subject to a mass target, considering the stress criterion. An initial design model is generated based on an actual FPSO riser support configuration. The topology optimization results present improved design performances under various loading conditions, while staying within the allowable limit of the offshore area.

• Journal of Information Technology Applications and Management
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• v.23 no.2
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• pp.81-95
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• 2016

Software export is very important for developing the domain software industry. Up to now, the study related in this issue is not enough even if exports are not activated. In our study, we treated and analyzed the three SME cases that have each successful record in recent years focusing to sales channels establishment and product localization. This study was done by interviewing the marketing directors mainly, and applied email exchanges, phones, and document analyses. Some implications can be addressed for the potential SME software exports. In the perspectives of sales channels building, the trust for product and firm itself is needed to have a good offshore partners. These are required to make the good relationship with partners, brand value's diffusion, and technical competency. As for product localization, the customization is important to meet the needs for local users effectively. So it is desirable to accept the advisory suggestions from the local consulting experts or representative customers. And the joint export strategy using the platform by linking some related products is effective for SME's software product's export.