• The Journal of Korean Physical Therapy
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• v.26 no.2
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• pp.97-103
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• 2014

Purpose: The aim of this study was to clarify the gender difference during standing balance in accordance with recruitment of abdominal muscles against sudden support surface translation. Methods: Twenty healthy males (n = 10, $26.50{\pm}3.54$ years, $170.60{\pm}6.30cm$, $72.80{\pm}5.69kg$) and females (n = 10, $24.40{\pm}2.63$ years, $163.00{\pm}4.97cm$, $52.10{\pm}4.41kg$) participated in the study. Each subject performed standing balance task on a platform, which moved in the anterior and posterior direction, with a total of 18 trials in three abdominal conditions (resting, hollowing, and bracing). We analyzed angular displacement of thoracic and lumbar spine and linear displacement of center of mass for evaluatione of spinal stability and standing balance, respectively. Results: Angular displacement of thoracic and lumbar spine and linear displacement of center of mass did not differ significantly between female and male in all conditions. Conclusion: Our results indicate that the ability to maintain spinal stability and standing balance were similar between male and female regardless of the abdominal contractile conditions and the direction of support surface translation.

• Geotechnical Engineering
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• v.6 no.2
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• pp.47-54
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• 1990

The accuracy of a limit equilibrium analysis of slope stability depends on the accuracy with which the strength properties and geometric conditions can be defined, and on the inherent accuracy of the method of analysis. Most of the slope stability analysis method have been computer coded, and this is a comparative study on the accuracy of these programs. Comparative analyses have shown that for the slopes with relatively simple conditions Host of the programs which are widely used in this country result in the same value of safety factor with an accuracy no worse than $\pm$5%. Similar results can be obtained from the examination of the several slope failure for which accurate information is available on the strength and geometric conditions of the earth slope. The critical failure surface, however, can be different from the actual slip surface, although nearly the same factors of safety are obtained from the analyses of each surface.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.5
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• pp.895-905
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• 2023

Mud tanks used for storing and supplying mud in mud supply systems are essential to secure structural stability according to the mud loads inside the tank. In terms of structural stability of the mud tank can be ensured by increasing the thickness of the structure. However, increasing the thickness may cause a problem of increasing production costs. In addition, this increases the weight of the tank, which can cause problems with the trailer loading weight limitation during transportation. To satisfy both these problems and structural stability, the mud tank should be optimally designed. Therefore, this study conducted an optimum design in consideration of the load of the mud tank through the structural analysis and response surface optimization method in ANSYS.

• Proceedings of the Korean Geotechical Society Conference
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• 1997.10a
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• pp.89-96
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• 1997

• Proceedings of the Membrane Society of Korea Conference
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• 2004.03a
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• pp.37-59
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• 2004

Advantages : - Multi-functionality of inorganic surface ㆍMetal chelating ligand $\longrightarrow$ metal recovery .Alkylation $\longrightarrow$ hydrophobicity control - Enhanced stability ㆍThermal, mechanical and chemical stability ㆍSeparation in high temperature and pressure (omitted)

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.193-194
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• 2008

$Orgacon^{TM}$ products, based on the conducting polymer PEDOT/PSS, are very promising materials in cost-effective R2R production of large area electronics. This presentation will show both the progress in the surface resistance/VLT and progress in the stability (T/R.H. and light stability). A new generation of films, coating formulations and inks will be presented.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.555-556
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• 2011

• Physical Therapy Korea
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• v.19 no.3
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• pp.61-71
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• 2012

In daily activities, people often perform two or more tasks simultaneously. This is referred to as dual-tasking or multi-tasking. The purpose of this study was to examine the effects of performing dual tasks while using a mobile phone on static and dynamic postural stability. Twenty-four subjects were asked to stand on a force plate and then instructed to perform a balance task only (BT), a balance task while listening to music (BTL), a balance task while talking on the mobile phone (BTT), and a balance task while sending text messages (BTS). We used the BioRescue$^{(R)}$ to measure postural sway and limit of stability for static and dynamic postural stability. Also the star excursion balance test (SEBT) was used to measure dynamic postural stability. A one-way ANOVA with repeated measures was used to compare the effects of the BT, BTL, BTT, and BTS. The Bonferroni's post hoc test was used to determine the differences among four tasks. Carrying out the BTS significantly decreased the limit of stability compared with carrying out the BT, BTL, and BTT (p<.05). In limit of stability, total surface area of BTT was more significantly decreased than that of BT and total surface area of BTS was more decreased than that of BT, BTL and BTT (p<.05). In the SEBT, the BTS displayed significantly smaller reach distance values compared with the BT or BTL (p<.05). These findings suggest that performing the balance task while sending text message on the mobile phone decreases dynamic postural stability, whereas performing the same task while listening to music using the mobile phone does not. Therefore, it requires more attention to maintain dynamic balance while sending text messages.

• Steel and Composite Structures
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• v.11 no.5
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• pp.423-434
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• 2011

Tongwamen Bridge is a critical link between Dongmen Island and the land in Shipu town, Zhejiang province, China. It is a 238 m span, half-through, concrete-filled steel tubular (CFST) X-type arch bridge. The width of the deck is only 10 m, yielding a width-to-span ratio of 1/23.8. The plane truss type section rib was adopted, which made of two CFST chords and web member system. The lateral stability is the key issue to this bridge. However, the existing researches on Tongwamen Bridge's lateral stability are all the deterministic structural analysis. In this paper, a new strategy for positioning sampling points of the response surface method (RSM), based on the composite method combining RSM with geometric method for structural reliability analysis, is employed to obtain the reliability index of lateral stability. In addition the correlated parameters were discussed in detail to find the major factors. According to the analysis results, increasing the stiff of lateral braces between the arch ribs and setting the proper inward-incline degree of the arch rib can enhance obviously the reliability of lateral stability. Moreover, the deck action of non-orienting force is less than the two factors above. The calculated results indicate that the arch ribs are safe enough to keep excellent stability, and it provides the foundation that the plane truss rib would be a competitive solution for a long-span, narrow, CFST arch bridge.

• Structural Engineering and Mechanics
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• v.89 no.3
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• pp.253-263
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• 2024

Slope stability is generally paid more attention to in slope protection works, especially for slope containing weak layers. Two indexes of safety factor and failure model are selected to perform slope stability. Moreover, the finite element limit analysis method comprehensively combines the advantage of the limit analysis method and the finite element method obtaining the upper and lower bounds of the safety factor and the failure mode under the slope stability limit state. In this study, taking a waste dump containing a weak layer as an engineering background, the finite element limit analysis method is adopted to explore the potential failure mode. Meanwhile, the sensitivity analysis of slope stability is performed on geometrical and geotechnical parameters of the waste dump. The results show that the failure mode of the waste dump slope is two wedges if the weak layer is located on the ground surface (Model A), while the slope can be observed as three wedges failure if the weak layer is below the ground surface (Model B). In addition, both failure modes are highly sensitive to the friction angle of the weak layer and the shear strength of waste disposal, and moderately sensitive to the heap height, the dip angle and cohesion of the weak layer, while the toe cutting has limited effect on the slope stability. Moreover, the sensitivity to the excavation of the ground depends on the location of the weak layer and failure mode.