• Smart Structures and Systems
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• v.22 no.5
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• pp.527-546
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• 2018

This article presents an analysis into the nonlinear forced vibration of a micro cylindrical shell reinforced by carbon nanotubes (CNTs) with considering agglomeration effects. The structure is subjected to magnetic field and transverse harmonic mechanical load. Mindlin theory is employed to model the structure and the strain gradient theory (SGT) is also used to capture the size effect. Mori-Tanaka approach is used to estimate the equivalent material properties of the nanocomposite cylindrical shell and consider the CNTs agglomeration effect. The motion equations are derived using Hamilton's principle and the differential quadrature method (DQM) is employed to solve them for obtaining nonlinear frequency response of the cylindrical shells. The effect of different parameters including magnetic field, CNTs volume percent and agglomeration effect, boundary conditions, size effect and length to thickness ratio on the nonlinear forced vibrational characteristic of the of the system is studied. Numerical results indicate that by enhancing the CNTs volume percent, the amplitude of system decreases while considering the CNTs agglomeration effect has an inverse effect.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.636-639
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• 1997

In this paper, a dynamic control scheme is proposed which not only compensates for the lateral dynamics and longitudinal dynamics but also deal with the yaw motion dynamics. Using the dynamic control technique, adaptive and learning algorithm together, the proposed controller is not only robust to disturbance and parameter uncertainties but also can learn the inverse dynamics model in steady state. Based on the proposed dynamic control scheme, a dynamic vehicle simulator is contructed to design and test various control techniques for 4-wheel steering vehicles.

• Communications for Statistical Applications and Methods
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• v.10 no.2
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• pp.423-432
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• 2003

The data observed at different positions are called the estimate of interested variable at new observation point on the Kriging utilize the space estimate technique, in which case there is correlation spatially. In this paper we provide the estimate for Variogram and Kriging methods as a field of kriging theory and dealt with actually measured data. And at the same time we forecast the amount of ozone that was not measured at this point by Kriging method and compared Ordinary Kriging method with Inverse Distance Kriging method.

• Journal of Ocean Engineering and Technology
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• v.17 no.5 s.54
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• pp.19-24
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• 2003

The question of wave source identification in a wave maker problem is the primary objective of the this paper. With the observed wave elevation, the existence of the wave maker velocity is discussed with the help of the mathematical theory of inverse problems. Utilizing the property of the Strum-Liouville system and compactness, the uniqueness and the ill-posedness(in the sense of stability) for the identification are proved.

• Korean Journal of Mathematics
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• v.19 no.1
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• pp.101-109
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• 2011

We get a theorem which shows that there exist at least two or three nontrivial weak solutions for the nonlinear parabolic boundary value problem with the variable coefficient jumping nonlinearity. We prove this theorem by restricting ourselves to the real Hilbert space. We obtain this result by approaching the topological method. We use the Leray-Schauder degree theory on the real Hilbert space.

• Structural Engineering and Mechanics
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• v.59 no.4
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• pp.761-774
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• 2016

Curved beams' dynamic behavior on viscoelastic foundation is the subject of the current paper. By rewritten the Timoshenko beams theory formulation for the curved and twisted spatial rods, governing equations are obtained for the circular beams on viscoelastic foundation. Using the complementary functions method (CFM), in Laplace domain, an ordinary differential equation is solved and then those results are transformed to real space by Durbin's algorithm. Verification of the proposed method is illustrated by solving an example by variating foundation parameters.

• Proceedings of the IEEK Conference
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• 2000.06e
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• pp.124-126
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• 2000

The Minimum-Norm Least-Square(MNLS) approach based on lead field theory is an useful method to find an unique inverse solution for the measured magnetic field. The lead field depends on head geometry and location of sources and sensors. So, optimization of sensor array location is important issue for MNLS estimation. In this paper, we present an investigation for the optimization of sensor array location in computer simulation.

• Journal of Distribution Research
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• v.16 no.3
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• pp.33-75
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• 2011

The ownership structure of a franchise system is determined by the franchisor's strategic choice. A close look at the extant theories and perspectives in economics and management such as resource scarcity theory, agency theory, transaction cost analysis, and mixed ownership theory reveals that firms choose their ownership structure for the sake of economic efficiency, profit potentials, the chance of survival, and other strategic concerns. The present study, on the basis of strategic choice perspective, reviews the divergent theories of a franchise system's ownership structure and its determinants, thus providing a theoretical framework for comparing the contradictory arguments along the several critical dimensions. We also developed and tested the conflicting hypotheses regarding key determinants of ownership structure including firm's age, size, transaction-specific investments, uncertainty, and risk-sharing propensity. Using a FDD (Franchise Disclosure Document) data set of 543 Korean franchisors, we found that the years in business, the total number of employees, days of training, the inverse of the years of franchising, and the requirement of royalty payment have positive relationships with the proportion of company-owned outlets to total number of outlets. On the other hand, the proportion of company-owned outlets was found to have negative relationships with the total number of outlets and the extent of geographic dispersion of outlets, but to have no significant relationships with the initial investment required and the inverse of contract length. Based on the findings, we provide several theoretical and managerial implications for studying ownership structure of franchise systems.

• Industrial Engineering and Management Systems
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• v.11 no.2
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• pp.183-187
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• 2012

In this paper, we study the fixed charge transportation problem with uncertain variables. The fixed charge transportation problem has two kinds of costs: direct cost and fixed charge. The direct cost is the cost associated with each source-destination pair, and the fixed charge occurs when the transportation activity takes place in the corresponding source-destination pair. The uncertain fixed charge transportation problem is modeled on the basis of uncertainty theory. According to inverse uncertainty distribution, the model can be transformed into a deterministic form. Finally, in order to solve the uncertain fixed charge transportation problem, a numerical example is given to show the application of the model and algorithm.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.3
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• pp.21-30
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• 2013

Powell-Miller theory is a good method to express or treat incorrect information. But it has limitation that requires too much time to apply to actual situation because computational complexity increases in exponential and functional way. Accordingly, there have been several attempts to reduce computational complexity but side effect followed - certainty factor fell. This study suggested expanded Approximation Algorithm. Expanded Approximation Algorithm is a method to consider both smallest supersets and largest subsets to expand basic space into a space including inverse set and to reduce Approximation error. By using expanded Approximation Algorithm suggested in the study, basic probability assignment function value of subsets was alloted and added to basic probability assignment function value of sets related to the subsets. This made subsets newly created become Approximation more efficiently. As a result, it could be known that certain function value which is based on basic probability assignment function is closely near actual optimal result. And certainty in correctness can be obtained while computational complexity could be reduced. by using Algorithm suggested in the study, exact information necessary for a system can be obtained.