• Journal of the Korean Society for Advanced Composite Structures
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• v.3 no.4
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• pp.17-26
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• 2012

This study presents a governing equations of bending behavior of anisotropic sandwich plates with multi-layered laminated composite faces. Based on zig-zag models for through thickness deformations, the shear deformation of composite faces is included. All edges of plate are assumed to be simply supported. Results of the bending analysis under lateral loads are presented for the influence of various lay up sequences of antisymmetric angle-ply laminated faces. The accuracy of the approach is ascertained by comparing solutions from the sandwich plates theory with composite faces to the laminated plates theory. Since the present analysis considers the bending stiffness of the core and also the transverse shear deformations of the laminated faces, the proposed method showed higher than that calculated according to the general laminated plates theory. The information presented might be useful to design sandwich plates structure with polymer matrix composite faces.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.04a
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• pp.83-86
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• 2004

The aeroelastic stability analysis of composite bearingless rotors is investigated using a large deflection beam theory in hover. The bearingless rotor configuration consists of a single flexbeam with a wrap-around type torque tube and the pitch links located at the leading edge and trailing edge of the torque tube root. For the analysis of composite bearingless rotors, flexbeam is assumed to be a rectangular section made of laminate. Two-dimensional quasi-steady strip theory and Loewy's aerodynamic theory with the lift deficiency function are used for unsteady aerodynamic computation. The finite element equations of motion for beams are obtained using Hamilton's principle. Numerical results of selected bearingless rotor configurations are obtained for the lay-up of laminae in the flexbeam and pitch links location.

• Korean Institute of Interior Design Journal
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• no.2
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• pp.40-45
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• 1994

This thesis is to research the change in attitude regarding the architectura ornament. One of the key dogmas within Modern Movement of art and design was anti-ornamentalism. The modernist had revolted against ornament and believed that the greatness of the modern age might lay in its inability to produce a new form of ornament. Architectural ornament has been passed through an process of evolution in a decadent stage. In this context, the purpose of this study is to identify historical meaning of architectural ornament in the age of transition toward Modernism.

• Journal of the Korean Institute of Rural Architecture
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• v.16 no.4
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• pp.9-15
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• 2014

Pungsu acts as a strong guideline for selecting a location of the village having a certain geographical condition. The attitude of choosing an auspicious site regarding the shape of mountains and water stream, is widely accepted by the intelligent class of Josen period. Therefore, the theory is one of the main factor influenced on the traditional village and house in Korea. Regarding the fact that a real effect of pungsu on the formation of traditional village and house, Study with a view of Pungsu theory could be a good method for deeply understanding the traditional architecture in Korea. In this context, the study analyzes the site and space lay out of an upper class house of vice minister Lee(Lee, Jung Ryul, 1868~1950) in Oeam historic village with Pungsu theory. The house is composed of Anchae(house for the women) and Sanrangchae(house for the men and receiving guests) and Hangrangchae(servants' quarters). Through the study, It finds out that the house is carefully selected and planned considering surrounding physical environment so called Jusan(back hill), Ansan(front hill), Choengyong(blue dragon) and Beckho(white tiger) of Pungsu theory.

• Journal of muscle and joint health
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• v.4 no.2
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• pp.177-196
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• 1997

This study was undertaken to explore the antecedent factors and process of the treatment-seeking behaviors of medical and alternative treatments in patients with arthritis using methodological triangulation. The data were collected from 995 arthritic patients who were registered either in a center of rheumatology for medical treatment or residents of community having no treatment to classify different treatment patterns. Sixteen patients with various types of treatment only, alternative treatment only, and no treatment were selected among the total samples to identify the antecedent factors through in-depth interview. The quantitative data were analyzed by percentile, t-test, chi-square test and discrimant analysis using SAS PC program, while the qualitative data were analyzed by means of grounded theory methodology. Treatment-seeking behaviors of patients change from the early stage to the sick-role stage. At the early stage, initial characteristics of pain and acculturation of medical professionalism affect the choice of treatment patterns. The acculturation of medical professionalism is affected by health care accessibility, level of education, duration of sickness and lay referral system. At the sick-role stage, lay referral system and acculturation of medical professionalism affect the choice of treatment patterns. The acculturation of medical professionalism is affected by characteristics of symtoms, perceived treatment effects, perceived causes of diseases and socio-economic status as well as health care accessibility, level of education and lay referral system. In conclusion, different factors as well as common factors are influencing the treatment-seeking behaviors depending on the disease and treatment stages. More detailed further studies are required to explore the value system or medical acculturation of patients which is one of the most important factors in decision-making about treatment modalities.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7679-7686
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• 2014

Background: This study aimed to seek insights into Chinese women's lay beliefs about cervical cancer causal attributions and prevention. Materials and Methods: Twenty-three new immigrant adult women from Mainland China and thirty-five Hong Kong adult women underwent semi-structured in-depth interviews. Interviews were audio taped, transcribed and analyzed using a Grounded Theory approach. Results: This study generated three foci: causal beliefs about cervical cancer, perceived risk of cervical cancer, and beliefs about cervical cancer prevention. Personal risky practices, contaminated food and environment pollution were perceived as the primary causes of cervical cancer. New immigrant women more likely attributed cervical cancer to external factors. Most participants perceived cervical cancer as an important common fatal female cancer with increased risk/prevalence. Many participants, particularly new immigrant women participants, expressed helplessness about cervical cancer prevention due to lack of knowledge of prevention, it being perceived as beyond individual control. Many new immigrant participants had never undergone regular cervical screening while almost all Hong Kong participants had done so. Conclusions: Some Chinese women hold pessimistic beliefs about cervical cancer prevention with inadequate knowledge about risk factors. Future cervical cancer prevention programs should provide more information and include capacity building to increase Chinese women's knowledge and self-efficacy towards cervical cancer prevention.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.05a
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• pp.126-129
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• 2001

LIPCA (LIghtweight Piezo-composite Curved Actuator) is an actuator device which is lighter than other conventional piezoelectric ceramic type actuator. LIPCA is composed of a piezoelectric ceramic layer and fiber reinforced light composite layers, typically a PZT ceramic layer is sandwiched by a top fiber layer with low CTE (coefficient of thermal expansion) and base layers with high CTE. LIPCA has curved shape like a typical THUNDER (thin-layer composite unimorph feroelectric driver and sensor), but it is lighter an than THUNDER. Since the curved shape of LIPCA is from the thermal deformation during the manufacturing process of unsymmetrically laminated lay-up structure, an analysis for the thermal deformation and residual stresses induced during the manufacturing process is very important for an optimal design to increase the performance of LIPCA. To investigate the thermal deformation behavior and the induced residual stresses of LIPCA at room temperature, the curvatures of LIPCA were measured and compared with those predicted from the analysis using the classical lamination theory. A methodology is being studied to find an optimal stacking sequence and geometry of LIPCA to have larger specific actuating displacement and higher force. The residual stresses induced during the cooling process of the piezo-composite actuators have been calculated. A lay-up geometry for the PZT ceramic layer to have compression stress in the geometrical principal direction has been designed.

• Structural Engineering and Mechanics
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• v.5 no.4
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• pp.433-450
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• 1997

The objective of this work is to predict the failure loads, associated maximum transverse displacements, locations and the modes of failure, including the onset of delamination, of thin, flat, square symmetric laminates under the action of uni-axial compression. Two progressive failure analyses, one using Hashin criterion and the other using Tensor polynomial criteria, are used in conjunction with the finite element method. First order shear deformation theory and geometric nonlinearity in the von Karman sense have been employed. Five different types of lay-up sequence are considered for laminates with all edges simply supported. In addition, two boundary conditions, one with all edges fixed and other with mixed boundary conditions for $(+45/-45/0/90)_{2s}$ quasi-isotropic laminate have also been considered to study the effect of boundary restraints on the failure loads and the corresponding modes of failure. A comparison of linear and nonlinear results is also made for $({\pm}45/0/90)_{2s}$ quasi-isotropic laminate. It is observed that the maximum difference between the failure loads predicted by various criteria depend strongly on the laminate lay-ups and the flexural boundary restraints. Laminates with clamped edges are found to be more susceptible to failure due to the transverse shear and delamination, while those with the simply supported edges undergo total collapse at a load slightly higher than the fiber failure load.

• Structural Engineering and Mechanics
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• v.6 no.2
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• pp.143-159
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• 1998

The objective of this present work is to estimate the failure loads, associated maximum transverse displacements, locations and the modes of failure, including the onset of delamination, of thin, square symmetric laminates under the action in-plane positive (+ve) shear load. Two progressive failure analyses, one using the Hashin criterion and the other using a Tensor polynomial criterion, are used in conjunction with finite element method. First order shear deformation theory along with geometric non-linearity in the von Karman sense have been employed. Variation of failure loads and failure characteristics with five type of lay-ups and three types of boundary conditions has been investigated in detail. It is observed that the maximum difference between failure loads predieted by various criteria depends strongly on the laminate lay-up and the flexural boundary restraint. Laminates with clamped edges are found to be more susceptible to failure due to transverse shear (ensuing from the out of plane bending) and delamination, while those with simply supported edges undergo total collapse at a load slightly higher than the fiber failure load. The investigation on negative (-ve) in-plane shear load is in progress and will be communicated as part-II of the present work.

• Steel and Composite Structures
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• v.48 no.6
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• pp.625-639
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• 2023

In this paper, a Taguchi-based finite element method (FEM) has been proposed and implemented to assess optimal design parameters for minimum static deflection in laminated composite plate. An orthodox mathematical model (based on higher-order shear deformation plate theory and Green-Lagrange geometrical nonlinearity) has been used to compute the nonlinear central deflection values of laminated composite plates according to Taguchi design of experiment via a self-developed MATLAB computer code. The lay-up scheme, aspect ratio, thickness ratio and the support conditions of the laminated composite plate structure were designated as the governable design parameters. Analysis of variance (ANOVA) is used to investigate the effect of diverse control factors on the nonlinear static responses. Moreover, regression model is developed for predicting the desired responses. The ANOVA revealed that the lay-up scheme alongside the support condition plays vital role in minimizing the central deflection values of laminated composite plate under uniformly distributed load. The conformity test results of Taguchi analysis are also in good agreement with the numerical experimentation results.