• Steel and Composite Structures
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• v.26 no.5
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• pp.607-620
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• 2018

Vibration analysis of deep curved FG nano-beam has been carried out based on modified couple stress theory. Material properties of curved Timoshenko beam are assumed to be functionally graded in radial direction. Governing equations of motion and related boundary conditions have been obtained via Hamilton's principle. In a parametric study, influence of length scale parameter, aspect ratio, gradient index, opening angle, mode number and interactive influences of these parameters on natural frequency of the beam, have been investigated. It was found that, considering geometrical deepness term leads to an increase in sensitivity of natural frequency about variation of aforementioned parameters.

• Steel and Composite Structures
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• v.26 no.1
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• pp.89-102
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• 2018

This work investigates a novel plate formulation and a modified couple stress theory that introduces a variable length scale parameter is presented to discuss the static and dynamic of functionally graded (FG) micro-plates. A new type of third-order shear deformation theory of Reddy that use only 4 unknowns by including undetermined integral variables is proposed in this study. The equations of motion are derived from Hamilton's principle. Analytical solutions are obtained for a simply supported micro-plate. Numerical examples are presented to examine the effect of the length scale parameter on the responses of micro-plates. The obtained results are compared with the previously published results to demonstrate the correctness of the present formulation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.260-267
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• 2002

For an elastically suspended rigid body with the planes of symmetry in a three dimensional space, a novel analysis fur the vibration modes is presented. From the decompositions of the stiffness and inertia matrices, the conditions for the existence of pure translation and pure couple modes are analyzed for an elastically suspended rigid body with the planes of symmetry. From this analysis, it can be showed that how the structure of stiffness and inertia must be related in order to produce the pure translation and pure couple modes when an elastically suspended rigid body has one, two, or three planes of symmetry.

• Journal of Families and Better Life
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• v.19 no.2
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• pp.1-12
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• 2001

The purpose of this study is to develop and evaluate family life education for meddle-aged man. We developed family life education program for man consisting of 4 sessions, which is based on the system theory and strong family perspective. The program was designed to contribute to making sound family culture and more to make more equal relation between a couple by breaking from the sex-types identity and recognizing androgyny. After implementing a program for 4 weeks, the quantity and quality evaluation revealed that the program made the middled-aged man have a chance to recognize the importance of their family, especially the need to respect wife, to reflect family role performance and to learn the importance of communication between a couple.

• Advances in materials Research
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• v.8 no.3
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• pp.219-235
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• 2019

This research is devoted to analyzing mechanical-thermal post-buckling behavior of a micro-size beam reinforced with graphene platelets (GPLs) based on geometric imperfection effects. Graphene platelets have three types of dispersion within the structure including uniform-type, linear-type and nonlinear-type. The micro-size beam is considered to be perfect (ideal) or imperfect. Buckling mode shape of the micro-size beam has been assumed as geometric imperfection. Modified couple stress theory has been used for describing scale-dependent character of the beam having micro dimension. Via an analytical procedure, post-buckling path of the micro-size beam has been derived. It will be demonstrated that nonlinear buckling characteristics of the micro-size beam are dependent on geometric imperfection amplitude, thermal loading, graphene distribution and couple stress effects.

• The Journal of Korean Obstetrics and Gynecology
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• v.31 no.3
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• pp.164-173
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• 2018

Objectives: This study aims to report the clinical effect of Korean medicine on infertile married couple. Methods: Four infertile married couples received Korean medicine therapies such as herbal medication, acupuncture and moxibustion. Results: After treatment, four couples were successful in spontaneous pregnancy. All patients gave birth to healthy babies. Conclusions: This study suggests that Korean medicine is effective in infertile married couple and shows possibility to increasing pregnancy rates.

• Journal of the Korean Home Economics Association
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• v.40 no.12
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• pp.159-170
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• 2002

This study, with a view to establishing the objective and concrete methodology of partition of properly by the married couple in the process of divorce, is to suggest the calculation method of impartial division of property by means of applying the system to division of remainder used in Germany. Generally, the process of estimating the amount of partitioned property has two steps, the first of which is to calculate the remainder of the husband and the wife each. The second step is to compare the remainders of the couple and calculate the difference in order for the spouse who has more to claim the payment of a half of the difference. This method has the advantage of dividing impartially the remainder obtained by labor in the married life.

• Journal of the Korean housing association
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• v.11 no.1
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• pp.89-102
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• 2000

This paper aims to analyze the changes in the structure of households with the eldery in Seoul and Taegu by time trands, using census data. The conclusions are as follows: The rate of the Single and Couple and Couple+Parent(s) Households with the eldery have been increasing. The rate of 3,4 generation households with the eldery has been decreasing. The trend towards single and Couple Households in Taegu was higher than that in Seoul. The result this paper is opposite to common knowledge that in general the speed of change in the large city is higher than that of in country town. And it is coincide with the results of the former papers of the writer.

• Structural Engineering and Mechanics
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• v.53 no.1
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• pp.105-130
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• 2015

In this paper, the classical continuum mechanics is adopted and modified to be consistent with the unique behavior of micro/nano solids. At first, some kinematical principles are discussed to illustrate the effect of the discrete nature of the microstructure of micro/nano solids. The fundamental equations and relations of the modified couple stress theory are derived to illustrate the microstructural effects on nanostructures. Moreover, the effect of the material surface energy is incorporated into the modified continuum theory. Due to the reduced coordination of the surface atoms a residual stress field, namely surface pretension, is generated in the bulk structure of the continuum. The essential kinematical and kinetically relations of nano-continuums are derived and discussed. These essential relations are used to derive a size-dependent model for Mindlin functionally graded (FG) nano-plates. An analytical solution is derived to show the feasibility of the proposed size-dependent model. A parametric study is provided to express the effect of surface parameters and the effect of the microstructure couple stress on the bending behavior of a simply supported FG nano plate.

• Wind and Structures
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• v.27 no.6
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• pp.431-438
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• 2018

This paper presents a free vibration analysis of size-dependent functionally graded (FG) nanobeams with all surface effects considerations on the basis of modified couple stress theory. The material properties of FG nanobeam are assumed to vary according to power law distribution. Based on the Euler-Bernoulli beam theory, the modeled nanobeam and its equations of motion are derived using Hamilton's principle. An analytical method is used to discretize the model and the equation of motion. The model is validated by comparing the benchmark results with the obtained results. Results show that the vibration behavior of a nanobeam is significantly influenced by surface density, surface tension and surface elasticity. Also, it is shown that by increasing the beam size, influence of surface effect reduces to zero, and the natural frequency tends to its classical value.