• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.438-439
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• 2006

We have used ITO/$Alq_3$/Al structure to study complex impedance in $Alq_3$ based organic light emitting diode. Equivalent circuit was analyzed in a device structure of ITO/$Alq_3$/Al by varying the thickness of $Alq_3$ layer from 60 to 400nm. The impedance results can be fitted using equivalent circuit model of parallel combination resistance $R_p$ and capacitance $C_p$ with a small series resistance $R_s$.

• Structural Engineering and Mechanics
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• v.41 no.1
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• pp.113-137
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• 2012

Frame structures with viscoelastic (VE) dampers mounted on them are considered in this paper. It is the aim of this paper to compare the dynamic characteristics of frame structures with VE dampers when the dampers are modelled by means of different models. The classical rheological models, the model with the fractional order derivative, and the complex modulus model are used. A relatively large structure with VE dampers is considered in order to make the results of comparison more representative. The formulae for dissipation energy are derived. The finite element method is used to derive the equations of motion of the structure with dampers and such equations are written in terms of both physical and state-space variables. The solution to motion equations in the frequency domain is given and the dynamic properties of the structure with VE dampers are determined as a solution to the appropriately defined eigenvalue problem. Several conclusions concerning the applicability of a family of models of VE dampers are formulated on the basis of results of an extensive numerical analysis.

• Tribology and Lubricants
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• v.38 no.5
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• pp.179-184
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• 2022

The power train of transmission for 21-ton grade wheel excavator makes use of a complex gear train composed of a planetary and helical gear system to drive the wheel excavator by transmitting power to the axle. The complex gear train with a shift mode is an important part of the transmission because of strength problems in an extreme environment. To calculate the specifications of the complex gear train and analyze the gear bending and compressive stresses of the complex gear train, this study analyzes gear bending and compressive stresses accurately for the optimal design of the complex gear train with respect to cost and reliability. In this article, the gear bending and compressive stresses of the complex gear train are calculated using the Lewes and Hertz equation. Evaluating the results with the data of the allowable bending and compressive stress from the stress and number of cycles curves of the gears verified the calculated specifications of the complex gear train. A computer structure analysis is performed with the 3D model of the planetary and helical gears to analyze the structure strength of the complex gear train. The results demonstrate that the durability and strength of the complex gear train are safe, because the safety factors of the bending and compressive stresses are more than 1.0.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.3004-3006
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• 2000

In this paper, we propose an optimal design method of Fuzzy-Neural Networks model with parallel structure for complex and nonlinear systems. The proposed model is consists of a multiple number of FNN connected in parallel. The proposed FNNs with parallel structure is based on Yamakawa's FNN and it uses simplified inference as fuzzy inference method and Error Back Propagation Algorithm as learning rules. We use a HCM clustering and GAs to identify the structure and the parameters of the proposed model. Also, a performance index with a weighting factor is presented to achieve a sound balance between approximation and generalization abilities of the model. To evaluate the performance of the proposed model. we use the time series data for gas furnace and the numerical data of nonlinear function.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.341-345
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• 2011

The Schiff base cobalt(II) complex, bis[4-chloro-2-((E)-(isopropylimino) methyl) phenol]cobalt(II), has been prepared and characterized by single-crystal X-ray diffraction analyses. The phenomenological, kinetic and mechanistic aspects of the cobalt (II) complex have been studied by TG/DTG techniques. On the basis of the experimental data, the kinetic parameters such as activation energy, pre-exponential factor and entropy of activation were computed, and then the most probable mechanism function was estimated as $g({\alpha})={\alpha}^2$ 2. Hence the rate controlling process at all stages of decomposition is onedimensional diffusion (Parabolic model).

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.9
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• pp.4307-4325
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• 2016

With the aim of solving the problems of long processing times, high memory consumption and low event throughput in the current processing approaches in out-of-order RFID event streams, an efficient complex event processing method based on INFA-HTS (Improved Nondeterministic Finite Automaton-Hash Table Structure) is presented in this paper. The contribution of this paper lies in the fact that we use INFA and HTS to successfully realize the detection of complex events for out-of-order RFID event streams. Specifically, in our scheme, to detect the disorder of out-of-order event streams, we expand the traditional NFA model into a new INFA model to capture the related RFID primitive events from the out-of-order event stream. To high-efficiently manage the large intermediate capturing results, we use the HTS to store and process them. As a result, these problems in the existing methods can be effectively solved by our scheme. The simulation results of our experiments show that our proposed method in this paper outperforms some of the current general processing approaches used to process out-of-order RFID event streams.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.3
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• pp.45-52
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• 2009

Generally, structures are analyzed as continuum. However, sometimes it is more efficient to analyze structure as a discrete model rather than as a continuum model in case of the structure has complex shape or loading condition. This study, therefore, suggests an improved analysis discrete model, named Equivalent Truss Model (further as "ETM"), which can obtain similar results with analyzing continuums analysis. ETM adopts a lattice truss to compose the members of the model, and analyses the structures. As a consequence, the ETM produced the identical outcome with the continuums analysis in section force of different structures and loading conditions. Similar results have been shown in internal stress analysis as well. Make use of that ETM is discrete, fractural path of beam was analyzed by ETM and the result was reasonable.

• Journal of Biomedical Engineering Research
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• v.10 no.2
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• pp.157-164
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• 1989

Three-dimensional imaging and manipulation of CT data are becoming increasingly important for deterRing the complex structure and pathologies. Octree which is a hierarchical data model is used to reconstruct three- dimensional objects from CT scans. Orthogonal cross sections are displayed by traverse the octree partially. Arbitrary oblique planes are derived by intersecting the square region of plane and cubic volume of octal node. Thia method enables the display of multi-structured complex organ ann the realization by personal computer.

• Journal of the Korean housing association
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• v.25 no.6
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• pp.39-47
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• 2014

The background of this study is to examine the structure of housing price of which characteristics are not equal but hierarchical in the apartment complexes. So, the purpose of this study is to analyze the influences of apartment complex characteristics on the housing price within the same regional boundary by HLM. The data used as dependent variables were the market prices of 938 units from 29 apartment complexes by stratified sampling. The 2nd level independent variables is the Housing complex characteristics which are composed of the housing complex & locational variables and the 1st level independent variables are the unit characteristics. The results are as follows. First, the first model shows that the 2nd level variables explains 68% of the housing prices. Second, the influential variables of the 1st level unit variable are 'dwelling exclusive area', 'floor of dwelling' and 'direction of dwelling'. Third, the influential variables of the housing complex variables in the 2nd level are 'lot area', 'the building-to-land ratio', 'the number of unit', 'the number of parking lots per unit', 'Green space area' and 'open space area per unit'. The last, the influential variables of the housing locational variables in the 2nd level are 'distance to subway and park' and the number of school and park within a radius of 1km.

• Smart Structures and Systems
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• v.15 no.1
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• pp.81-97
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• 2015

Recently, a new output-only modal identification method based on time-frequency independent component analysis (ICA) has been developed by the authors and shown to be useful for even highly-damped structures. In many cases, it is of interest to identify the complex modes of structures with non-proportional damping. This study extends the time-frequency ICA based method to a complex ICA formulation for output-only modal identification of non-proportionally-damped structures. The connection is established between complex ICA model and the complex-valued modal expansion with sparse time-frequency representation, thereby blindly separating the measured structural responses into the complex mode matrix and complex-valued modal responses. Numerical simulation on a non-proportionally-damped system, laboratory experiment on a highly-damped three-story frame, and a real-world highly-damped base-isolated structure identification example demonstrate the capability of the time-frequency complex ICA method for identification of structures with complex modes in a straightforward and efficient manner.