• Geomechanics and Engineering
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• v.29 no.6
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• pp.667-681
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• 2022

This paper presents a thermoelastic analysis of variable thickness plates made of functionally graded materials (FGM) subjected to mechanical and thermal loads. The thermal load is applied to the plate as a temperature difference between the top and bottom surfaces. Temperature distribution in the plate is obtained using the steady-state heat equation. Except for Poisson's ratio, all mechanical properties of the plate are assumed to vary linearly along the thickness direction based on the volume fractions of ceramic and metal. The plate is resting on an elastic foundation modeled based on the Winkler foundation model. The governing equations are derived based on the third-order shear deformation theory (TSDT) and are solved numerically for various boundary conditions using the differential quadrature method (DQM). The effects of various parameters on the stress distribution and deflection of the plate are investigated such as the value of thermal and mechanical loads, volume fractions of ceramic and metal, and the stiffness coefficients of the foundation.

• Journal of Distribution Science
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• v.14 no.2
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• pp.135-144
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• 2016

Purpose - The purpose of this paper is to empirically investigate the moderating effects of social capital on antecedents factors path of export performance in the materials and components SMEs(Small and Medium-sized Enterprises) of Busan and Kyungnam region. In case of materials and components SMEs, they are always trying to achieve business performance including export sales and market share, but it is difficult for them to increase performance due to the limitation of inner & tangible resources. Therefore intangible asset such as technology capability and its antecedents factors which are technology innovation and learning orientation are getting more important to SMEs. In addition, it is supposed that social capital such as local network including distribution channel in overseas market plays an essential role to enhance export performance. Accordingly, the main goal of this study is to find out the relationship between export performance and antecedents factors and the validity of social capital as a moderating valuable. Research design, data, and methodology - Technology innovation, learning orientation and technology capability have been used as antecedents factors for export performance and social capital such as network diversity and intensity has been used for moderating effects analysis. In order to select these valuables mentioned above, this study examined the existing researches on a basis of Resources Based View, Organizational Learning Theory and Social Capital theory. To achieve the objective of this paper, 7 hypotheses including the moderating effects have been proposed with 6 potential variables measured by 24 questions. The survey was carried out from December 2014 to March 2015 and 137 samples out of total 175 were selected for the analysis. PLS(Partial Least Squares) has been used for the methodology of empirical analysis for both antecedents factors path and moderating effects. Results - Research findings are as follows. First, technology innovation has a significant impact on learning orientation, learning orientation has a positive effect on the technology capability and technology capability also has a significant impact on export performance. Therefore 3 valuables are proved as antecedents factors of export performance. Second, the social capital(both network diversity and intensity) plays a moderating role with learning orientation to technology capability. However, there is no moderating effects between both of social capital and technology capability regarding export performance. Conclusions - According to path analysis results, it is suggested that the materials and components SMEs should raise technology innovation and learning orientation in order to improve technology capability and export performance. Meantime, the moderating effect analysis shows that SMEs should consider local network diversity and intensity along with learning orientation to add up technology capability. But local network diversity and intensity does not work systematically with technology capability for export performance and it means that SMEs should find the appropriate local partners for the purpose of establishing concrete distribution channels based on marketing perspective, not for improving technology capability.

• Journal of Korean Society of Steel Construction
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• v.10 no.3 s.36
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• pp.463-472
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• 1998

The purpose of this paper is to analyze the buckling characteristics of rigidly-jointed single-layer latticed domes with square network by using the experimental and the theoretical techniques in order to develop a reasonable method of theoretical analysis for these domes. Two methods of theoretical analysis are applied; one is based on the Yamada's method of shell analogy and the other is based on the frame analysis method using the finite element method. The effects of the nonuniformity of rigidity-distribution in the circumferential direction and the rigidity of the covering material on both the prebuckling and the buckling characteristics are examined. The results indicate that these effects should be considered reasonably in the theoretical analyses.

• Journal of Environmental Impact Assessment
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• v.2 no.2
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• pp.59-71
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• 1993

Evaluation methods are employed in environmental impact assessment to choose between different project site, to determine the required measures to compensate impact and to decide whether the environmental impacts are more important than the social or economic effects of a project. The main obstacles that restrict use of quantitative evaluation method are a Lack of knowledge about the environmental effects (e.g. if impacts on wildlife or landscape amenities are predicted) and the relative importance of economic and social issues compared with nature conservation stability of ecosystem or landscape beauty. In Germany, the most common method for site planning is the "ecological risk analysis". It is a kind of multi-criteria-decision-method based on quantitative and qualitative description and ordinal ranking. The various kinds of "ecological balancing methods" that are more recently developed (within the last decade) to quantify the required amount for compensatory measures instead often use cardinal figures to express the value of ecosystems, the intensity of impacts, the need for additional measures to compensate for long recuperative periods when restoring ecosystems and so on. There are still only a view attempts to quantify decisions between environmental and socio-economic issues. Multicriteria-analysis as well as cost-benifit-analysis was used. Some new approaches which are still in a preliminary status are based on contingent valuation and on calculations for compensatory payments (instead of compensatory measures).

• Korean Journal of Organic Agriculture
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• v.24 no.3
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• pp.369-383
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• 2016

Crop yield insurance program in Korea has rapidly grown not only in quantity but in quality for 15 years since it was introduced in 2001. Despite growth of Crop insurance, performance evaluation for crop yield insurance has not fully been evaluated at the farm, consumer and national level. The purpose of this study is to conduct the performance evaluation for crop yield insurance through estimating the effects of farm revenue stabilization and social welfare increase with three popular insurance items: apple, pear and sweet persimmon. Based on the analysis of social welfare effect, cost-benefit analysis of operating crop yield insurance was conducted at the national level. We found that crop yield insurance stabilizes farm revenue based on the estimated four risk indicators: Coefficient of Variation, Value at Risk, Certainty Equivalence, and Risk Premium. The result of cost-benefit analysis shows that crop yield insurance increases social net benefit by 44.1 billion won for the three items. As a result, crop yield insurance program has contributed remarkably on social welfare as well as farm management and its role will be more important in the future.

• Journal of the Korean Geotechnical Society
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• v.15 no.5
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• pp.19-28
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• 1999

In this paper, an application of finite element procedure for the analysis of slope failure behavior has been studied. The most widely accepted methods in analyzing the slope stability problems are mostly based on limit equilibrium method. And the finite element method is widely accepted to analyze stress and displacements. This paper shows how the factor of safety calculated in the finite element method can be systematically incorporated into slope stability. In analyzing the slope failure behavior by finite element method, the effects of computational method and the results have been discussed. And several computations of slope stabilities were carried out to compare the finite element analysis results with those obtained by methods of slices based on the limit equilibrium analysis.

• Journal of the Society of Naval Architects of Korea
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• v.41 no.2
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• pp.106-113
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• 2004

The block assembly of ship consists of a certain type of heat processes such as cutting, bending, welding, residual stress relaxation and fairing. The residual deformation due to welding is inevitable at each assembly stage. The geometric inaccuracy caused by the welding deformation tends to preclude the introduction of automation and mechanization and needs the additional man-hours for the adjusting work at the following assembly stage. To overcome this problem, a distortion control method should be applied. For this purpose, it is necessary to develop an accurate prediction method which can explicitly account for the influence of various factors on the welding deformation. Systematic and quantitative theoretical works to clarify the effects of various factors on the welding deformation have rarely been found. Therefore, in this paper, the effects of various factors, such as welding process and gravity on the butt welding deformation have been investigated through a number of numerical analyses. In addition, this paper proposes a simplified analysis method to predict the butt welding deformation in actual plate structure. For this purpose, a simple prediction model for butt welding deformations has been derived based on numerical and experimental results through the regression analysis. Based on these results, the simplified analysis method has been applied to some examples to show its validity.

• Journal of International Academy of Physical Therapy Research
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• v.11 no.3
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• pp.2164-2172
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• 2020

Background: Stroke patients have multiple disorders, but most have problems with balance and gait. Post-stroke rehabilitation exercise has been shown to be very important for functional recovery. Objectives: To systematically review and meta-analyze the effects of sling exercise (SE) on patients with stroke in studies published in Korea. Design: Meta-analysis. Methods: Five databases, namely, RISS, KISS, NDSL, DBpia and Earticle, were used to collect articles on vibration. Keywords such as "Stroke," "Hemiplegia," "Sling," and "Sling Exercise" were used in the search for published articles. Interventions and comparisons were SE and other exercise (OE). Outcome measures were berg balance scale (BBS) and timed up and go (TUG). Consequently, eight studies were selected in the second screening using meta-analyses. Results: Based on the results of the meta-analysis, SE was effective for BBS in the comparison of SE and OE [2.71, 95% CI (1.42, 4.01)]. It was effective for TUG in the comparison of SE and OE [-1.89, 95% CI (-3.01, -0.77)]. Conclusion: Based on eight limited studies, SE improved BBS and TUG over OE, suggesting improved stroke balance and gait. Therefore, more studies and large-scale sample randomized controlled trials are needed to confirm clinical application.

• Steel and Composite Structures
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• v.32 no.5
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• pp.657-670
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• 2019

This paper proposes a one-dimensional fiber beam element model taking account of materially non-linear behavior, benefiting the highly efficient elastic-plastic analysis of girders with shear-lag effects. Based on the displacement-based fiber beam-column element, two additional degrees of freedom (DOFs) are added into the proposed model to consider the shear-lag warping deformations of the slabs. The new finite element (FE) formulations of the tangent stiffness matrix and resisting force vector are deduced with the variational principle of the minimum potential energy. Then the proposed element is implemented in the OpenSees computational framework as a newly developed element, and the full Newton iteration method is adopted for an iterative solution. The typical materially non-linear behaviors, including the cracking and crushing of concrete, as well as the plasticity of the reinforcement and steel girder, are all considered in the model. The proposed model is applied to several test cases under elastic or plastic loading states and compared with the solutions of theoretical models, tests, and shell/solid refined FE models. The results of these comparisons indicate the accuracy and applicability of the proposed model for the analysis of both concrete box girders and steel-concrete composite girders, under either elastic or plastic states.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1420_1422
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• 2009

Lightning currents are one of major influences on the dynamic performance of counterpoise. High lightning current causes the dynamic grounding performance of counterpoise due to very fast fronted pulses. The previous analysis has often been based on quasi-static approximation that can not be applicable to very fast fronted pulses. To extend the analysis for fast fronted pulses in this paper, the full-wave analysis method based on the rigorous electromagnetic-field theory approach is used and the effects of the ionization of the soil are disregarded. Based on the simulation results, the empirical formulas applicable for slow and fast fronted lightning current pulses are reviewed; therefore, the validity of the theoretical approach is verified through comparison between the calculated and measured results.