• Smart Structures and Systems
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• v.5 no.5
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• pp.531-546
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• 2009

In the present analysis, the spline finite strip with higher-order shear deformation is formulated for the static analysis of piezoelectric composite plates. The proposed method incorporates Reddy's third-order shear deformation theory, Touratier's "Sine" model, Afaq's exponential model, Cho's higher-order zigzag laminate theory, as well as the classic plate theory and the first-order plate theory. Thus, the analysis can be conducted based on any of the above-mentioned theories. The selection of a specific method is done by simply changing a few terms in a 2 by 2 square matrix and the results, obtained according to different plate theories, can be compared to each other. Numerical examples are presented for piezoelectric composite plates subjected to mechanical loading. The results based on different shear deformation theories are compared with the three-dimensional solutions. The behaviours of piezoelectric composite plates with different length-to-thickness ratios, fibre orientations, and boundary conditions are also investigated in these examples.

• Korean Journal of Remote Sensing
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• v.19 no.2
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• pp.149-157
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• 2003

In this study, for efficient replacement of sensor modelling of high-resolution satellite imagery, image segmentation method is applied to the test area of the SPOT-3 satellite imagery. After that, a third-order polynomial model in the sectioned area is compared with the RFM which Is to the entire in the test area. As results, plane error of the third-order polynomial model is lower(approximately 0.8m) than that of RFM. On the other hand, height error of RFM is lower(approximately 1.0m).

• Proceedings of the Korea Society for Simulation Conference
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• 2005.11a
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• pp.45-50
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• 2005

Research and development of grid computing ware mainly focused on high performance computing field such as large-scale computing operation. Many companies and organizations concentrated on existing computational grid. However, service grid focusing on enterprise environments has been noticed gradually. Grid service providers of service grid construct diverse and specialized services and provide service resources that have economic feasibility to grid users. But, service resources are geographically dispersed and divided into many classes and have individual owners and management policies. In order to utilize and allocate resources effectively, service grid needs a resource management model that handles and manages heterogeneous resources of service grid. Therefore, this paper presents the third party grid service marketplace model using virtualization to solve problems of grid service resource management. Also, this paper proposes resource dealing mechanism and pricing algorithms applicable for service grid. Empirical results show usefulness and efficiency of the third party grid service marketplace model in comparison with typical economic models for grid resource management such as single auction model and double auction model.

• Journal of the Korean Society for Precision Engineering
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• v.4 no.3
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• pp.35-43
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• 1987

A new analytic method for the identification of process control system is presented. A second and a third order transfer function are considered as the estimated model function. For the second order transfer function, the new method is compared with the exisiting ones, simulation results show that the new method is superior to the existing ones. And also, In case of the third order transfer function which is difficult to analyze mathematically, system identification is tried.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.26.2-26
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• 2001

It is known that Volterra kernel model can represent a wide variety of nonlinear chemical processes. But almost all Volterra kernel models which appeared in the literature are up to second order, because it was difficult to measure higher order Volterra kernels. Kashiwagi has recently shown a method for measuring Volterra kernels up to third order using pseudorandom M-sequence signals. In this paper, the authors verified the applicability of this method for chemical processes using polymerization reactor simulation. Also, the authors have recently proposed a practical Identification method for chemical processes, which is based on the combination of off-line nonlinear identification and on-line linear identification. This method is also applied to the identification of polymerization reactor, and we obtained ...

• Journal of the Korean Statistical Society
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• v.24 no.2
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• pp.519-536
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• 1995

In the design of experiments for response surface analysis, sometimes it is of interest to estimate the difference of responses at two points. If differences at points close together are involved, the design that reliably estimates the slope of response surface is important. This idea was conceptualized by slope rotatability by Hader & Park (1978) and Park (1987). Until now, second order polynomial models were only studied for slope ratatability. In this paper, we will propose the necessary and sufficient conditions for slope rotatability over all directions for the thired order polynomial models in two, three and four independent variables. Also practical slope rotatable designs over all directions for two independent variables are suggested.

• Advances in nano research
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• v.6 no.2
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• pp.93-112
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• 2018

An analytical solution of the buckling governing equations of functionally graded piezoelectric (FGP) nanobeams obtained by using a developed third-order shear deformation theory is presented. Electro-mechanical properties of FGP nanobeam are supposed to change continuously in the thickness direction based on power-law model. To capture the small size effects, Eringen's nonlocal elasticity theory is adopted. Employing Hamilton's principle, the nonlocal governing equations of a FG nanobeams made of piezoelectric materials are obtained and they are solved using Navier-type analytical solution. Results are provided to show the effect of different external electric voltage, power-law index, nonlocal parameter and slenderness ratio on the buckling loads of the size-dependent FGP nanobeams. The accuracy of the present model is verified by comparing it with nonlocal Timoshenko FG beams. So, this study makes the first attempt for analyzing buckling behavior of higher order shear deformable FGP nanobeams.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1443-1448
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• 2003

Model Predictive Control (MPC) has recently found wide acceptance in industrial applications, but its potential has been much impounded by linear models due to the lack of a similarly accepted nonlinear modelling or data based technique. The authors have recently developed a new method for obtaining Volterra kernels of up to third order by use of pseudorandom M-sequence. By use of this method, nonparametric NMPC is derived in discrete-time using multi-dimensional convolution between plant data and Volterra kernel measurements. This approach is applied to an industrial polymerisation process using Volterra kernels of up to the third order. Results show that the nonparametric approach is very efficient and effective and considerably outperforms existing methods, while retaining the original data-based spirit and characteristics of linear MPC.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.98-101
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• 1998

The intermodulation distortion(IMD) due to laser diode nonlinearity of an asynhcronous direct sequence code diviion multiple access(DS/CDMA) system in wireless-optical transmission system model is analzed. A third order polynomial is used to represent laser diode nonlinearity. In DS/CDMA system, only one harmonic of the third-order intermodulation term falls on the signal frequency band and influences the system performance characteristics. To cancel multi-user interference and nonlinear distortion in a DS/CDMA wireless-optical transmission system model, the simple transversal filter structure with N-taps of (N-1) tap delay of 1 chip time delay line is used. It is necessary to select an optimal modulation index that provides a maximum signal-to-noise ratio and the results are useful for CDMA system design.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.4
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• pp.865-875
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• 1988

A two-dimensional stepped wall jet was numerically investigated by applying three different models : One is the standard k-.epsilon. and the other is the modified k-.epsilon. model which takes account of the streamline curvature effect by modifying the Reynolds shear stress and a source term in the dissipation equation, and a third is curvature dependent third-order correlation model. In order to test the influences of the numerical result, both the upwind scheme and the skew-upwind scheme were sued for the computations. By comparing the numerical results with available experiments, it was found that the modified k-.epsilon. model gives best overall prediction accuracy only when the numerical diffusion is eliminated by using the skew-upwind scheme. The numerical scheme was found to have more pronounced effect on the accuracy of the turbulence computation than the turbulence models.