• Composites Research
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• v.28 no.4
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• pp.204-211
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• 2015

This paper presents a theory related to a two-dimensional linear cross-sectional analysis, recovery relationship and a one-dimensional nonlinear beam analysis for composite wing structure with initial twist. Using VABS including a related theory, the design process of the composite rotor blade has been described. Cross-sectional analysis was performed at cutting point including all the details of geometry and material. Stiffness matrix and mass matrix were linked to each section to make 1D beam model. The 3D strain distributions within the structure were recovered based on the global behavior of the 1D beam analysis and visualize numerical results.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.816-821
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• 2005

The cycloid reducer has very high efficiency, high ratios, high stiffness and small size, in comparison with a conventional gear mechanism, which makes it an attractive candidate for limited space and precision application such as industrial robot. There are several publications on analysis and design of the cycloid reducer, however, it was assumed that the contact stiffness of pin rollers and cycloid disk is constant regardless of their contact geometry. Moreover, the torsional stiffness of the cycloid reducer couldn't be calculated due to the assumption. In this paper, we present a new procedure of calculating torsional stiffness of the cycloid reducer using Hertz contact theory. First, conventional force analysis of the cycloid reducer is briefly reviewed. Then, iterative numerical calculation procedure of the contact stiffness is proposed based on the Hertz contact theory where the contact stiffness depends on the contact force. In addition, total torsional stiffness of the cycloid reducer is estimated considering its rolling element bearing stiffness. The torsional stiffness of the cycloid reducer is dominated by the rolling element bearing stiffness since the contact stiffness of the cycloid disk is too large.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.1
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• pp.3-12
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• 2015

Bursting stress in anchorage zone of post tension girder can be estimated based on Guyon's equation. The major parameters in calculating bursting stress are prestressing force and the distance ratio between concrete edge and anchorage plate. Although Guyon's equation can be applied to calculate bursting stress for rectangular typed as well as circular typed plate, there is some limitation of accuracy due to 2 dimensional analysis. Therefore this study is proposed to suggest a bursting stress equation based on 3 dimensional finite element method.

• Journal of the Korean Home Economics Association
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• v.40 no.12
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• pp.1-11
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• 2002

This paper is intended as an analysis of the Chapter on Family in textbooks of a Middle school course at the aspect of Parson's Structural Functionalism Theory. In this analysis, We'd like to explore how the value of family is expressed in the Art-Home Economics textbooks. Generally, family is a subsystem in the structural system of whole society and family has two main functions to promote stability and equilibrium from the Parson's Structural Functionalism Theory point of view. Today, the concern with the Structural Functionalism Theory is dominantly reflected in textbooks, even though it has been proposed that the Structural Functionalism is not appropriate to explain family of modem society. Like that, the question now arises: the family history and interaction is ignored in the Structural Functionalism Theory. That is to say, There are limitations of Structural Functionalism Theory. The textbooks of Art-Home Economics was based on the revised curriculum has been severely changed in terms of external system of textbooks. But, we didn't know how much the view of the Structural Functionalism Theory is involved in textbooks. In this article, we analyze the view of the Structural Functionalism Theory in the Art- Home Economics textbooks using the Contents Analysis. At the same time, we find the confusion of family value revealed in textbooks.

• Journal of the Society of Naval Architects of Korea
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• v.31 no.1
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• pp.142-154
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• 1994

In this paper, stochastic imperfection sensitivity analyses of stiffened cylindrical shells under static load are presented. Multimode formulation is performed for the buckling load calculation based on the Donnell's theory and Galerkin approximation. Random imperfection field theory and response surface method are combined with deterministic bucking analysis scheme to perform stochastic imperfection sensitivity analyses of stiffened cylindrical shells considering random geometric imperfection. From the characteristics of probabilistic bucking load, the relation between reliability index and safety parameter can be obtained in addition to the relation between load and reliability index. Those results can be used to determine the range of required safety parameter and acceptable imperfection.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.05a
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• pp.205-208
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• 2001

Localized shear band is investigated through the analysis of one-dimensional model for simple shearing deformation of thermally rate dependent material. Generally mesh size or interval of nodes play an important role in determining the overall flow behavior of the material. In order to observe these size effects we adapted non-local theory by including higher order strain gradients of the equivalent strain into the constitutive equation for the flow stress. for the ease of convergence and numerical stability the inplicit finite difference scheme is employed.

• Journal of Advanced Navigation Technology
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• v.15 no.3
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• pp.449-455
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• 2011

In this paper, Proposed controller prevent compressor surge and reduce the acceleration time of the fuel flow control system for turbo-jet engine. Turbo-jet engine controller is designed by applying fuzzy PI+D control algorithm and make an inference by applying Mamdani's inference method and the defuzzification using the center of gravity method. Fuzzy inference results are used as the fuel flow control inputs to prevent compressor surge and flame-out for turbo-jet engine and the controller is designed to converge to the desired speed quickly and safely. Using MATLAB to perform computer simulations verified the performance of the proposed controller.

• Spatial Information Research
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• v.14 no.4 s.39
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• pp.403-419
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• 2006

The well-blown address matching technology developed by the U.S. Census Bureau was applicable only for street addresses. However, many other addressing systems on the basis of a hierarchy of areas (hierarchical areal addressing system), such as Korean or Japanese addressing system, cannot be suitable for the existing address matching method. This paper, therefore, develops an areal address matching method, especially for Korean addressing system, in order to geocode 2D and 3D locational data of human activities. Thus, this study explains a new approach to dealing with 3D positioning method composed of two geocoding methods, which are a '2D Korean Address Matching' technique and a '3D Address Matching' technique.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.1 s.256
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• pp.11-17
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• 2007

In this paper, we present a design, analysis, fabrication and performance test of the novel DoD metal-jet system for application to the high-density and high-temperature-melting materials. The theoretical analysis of the metal-jet nozzle system is derived by using electro-mechanical analogy. Based on the theoretical analysis results, we design the metal-jet print head system and fabricate the metal-jet system, which can eject the droplet of lead-free metal solder in high-temperature. In the experimental test, we set up the test apparatus for visualization of the droplet ejection and measure the ejected droplet volume and velocity. As a result, the diameter, volume and the velocity of the ejected droplet are about 65 $\mu$m $\sim$ 70 $\mu$m, 145p1 $\sim$ 180 pl and 4m/s, which shows quite good agreement with the theoretical analysis results of the 75 $\mu$m-diameter and 220 pl-volume of droplet. In comparison with the experimental result, the errors of diameter and volume are 7% $\sim$ 13% and 18 $\sim$ 34%, respectively.

• Cartoon and Animation Studies
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• s.36
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• pp.45-74
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• 2014

We can anticipate that animations will form one of the axes and lead popular culture in our future visual age. Recently, research has been actively conducted, but it mainly focuses on their value in culture industry or technologies and methods of producing animations. Of course, research that deals with animation characters has constantly come out. This study focuses on the 'formative elements' of 3D animation characters and attempts differentiation from other research by inducing new logic theoretically. Being freed from the research on characters that has been merely focused on theoretical grounds, this study intends to figure out how audience that is consumers who actually get to watch and feel animations recognizes them and find out related problems and also solutions for them. In particular, this study intends to examine the formative characteristics of 3D animation characters with the characters appearing in , one of the animations that have achieved artistic value as well as commercial success. And for that, the study conducted not only literature review but various surveys and Delphi method as well. Also, the researcher devised an analysis frame to evaluate the formative elements through in-depth discussion with experts. And with this, the study created the forms such as the Elements of Form, Formation Methods of Form and Visual Recognition Elements of Form, examined how audience recognized 3D characters. The process of recognizing an image is influenced by socio-cultural environment or sex, age, and the level of knowledge differently. This was meant to investigate current visual culture and the public's perspective through characters in that represent the visual mode.