• Journal of Adhesion and Interface
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• v.12 no.2
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• pp.47-55
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• 2011

UV-curable coatings have been used in various industries due to their advantages such as high mechanical property, good solvent resistance, fast curing process and low volatile organic compounds. However, a lack of flexibility of UV-cured films is a weak point for the pre-coated system of roll-to-roll process. In this study, UV-curable polycarbonate-based methacrylates were synthesized with polycarbonate diol, isophorone diisocyanate and 2-hydroxyethylmethacrylate to improve flexibility of the UC-cured films. The effects of polyol molecular weight, content of photoinitiator and monomers on the UV-curing behavior, flexibility and properties were investigated. The UV-curing behavior was measured by a photo-DSC, the pendulum hardness, tensile strength, viscoelastic properties were also evaluated.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.197.2-197.2
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• 2005

• Geomechanics and Engineering
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• v.36 no.6
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• pp.527-543
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• 2024

In the implementation of most civil structures, especially underground, deep excavations with a vertical slope are required. Using flexible retaining walls is applied as one of the ways to stabilize vertical holes. Therefore, it is necessary to know the parameters affecting the performance of such walls in reducing their horizontal movement. In this research, by building a suitable laboratory model, the parameters of the amount of flexibility, the embedment depth of the wall, the type and number of tieback in the wall were investigated for 42 static laboratory models. The purpose of this research is to study the flexible retaining wall with helical tieback compared to simple tieback at different heights, which shows the best performance in terms of reducing horizontal displacement in proportion to increasing or decreasing flexibility. On the other hand, one of the parameters affecting the flexibility of the wall, which is its bending stiffness, was extracted by numerical software outputs and studied on the results such as relative flexibility, stiffness, safety and numerical stability of the wall.The results of this study show that among the parameters, in the first place, the effect of the type of tieback is inhibited and in the second place, the ratio of thickness to wall height is known as the most important parameter. the best performance for walls with the helical tiebacks in reducing their horizontal displacement can be economically, flexibly and stability assigned to a wall that tiebacks is in the range of H2/t to H4/t and its flexibility ratio is 2/3.

• The Journal of Korean Medicine
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• v.32 no.6
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• pp.103-111
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• 2011

Objectives: The study was investigated to assess efficacy for home visiting treatment using Traditional Korean Medicine (TKM). Methods: The traditional medical doctor of Um-Sung health center has treated the 109 patients and they also answered the questionnaires of home visiting treatment using TKM before and after. The questionnaires were composed of flexibility, pain, health behavior, perception of health, satisfaction, cognition of TKM, etc. The questionnaires were analyzed by use of paired t-test and chi-square test. Results: They have significantly improved the flexibility (p<.001), pain (p<.001), health behavior (p<.001), and the perception (p<.001) of health after home visiting treatment. It was also brought to improve about the perception of TKM, and showed a good satisfaction and the improvement of health. Conclusion: Home visiting treatment using TKM is helpful to improve the health based on these results. We need to systemize the research for the activation of home visiting treatment using TKM.

• Composites Research
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• v.12 no.6
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• pp.83-89
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• 1999

The impact strength and fracture behavior of rubber/polymer composites were investigated with respect to two factors: (i) characteristic ratio, $C_{\infty}$ as a measure of chain flexibility of the polymer matrix and (ii) the rubber particle size in polymer blend system. In this study C was controlled by the composition ratio of polyphenylene oxide (PPO) and polystyene (PS). Izod impact test and fractographic observation of the fracture surface using scanning electron microscope were conducted. Finite element analysis were carried out to gain understanding of plastic deformation mechanism (shear yielding and crazing) of these materials. Shear yielding was found to be enhanced when the flexibility of matrix polymer was relatively low and the rubber particles were small.

• Journal of muscle and joint health
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• v.21 no.2
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• pp.114-124
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• 2014

Purpose: The purpose of this study was to explore the effects of the 8-weeks back pain management program (consisted of exercise and education for back pain) in patients with chronic low back pain. Methods: A total of 20 subjects who visited the pain clinic in a university hospital were randomly assigned either to a experimental or a control group. Ten subjects in the experimental group carried out the back pain management program for 8 weeks, and 10 in the control group did not. Results: After the back pain management program, back pain and disability were significantly reduced, and back pain management behavior and back muscle strength were significantly increased in the experimental group. However, radiating pain and flexibility were not significantly changed after the back pain management program. Conclusion: Findings of this study indicated that the 8-weeks back pain management program had favorable effects on back pain, degree of disability, back pain management behavior, and back muscle strength in patients with chronic low back pain. Future research needs to examine the optimal intensity and frequency of back muscle strengthen exercise, and the lasting effects of education for back pain.

• Geomechanics and Engineering
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• v.9 no.1
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• pp.39-55
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• 2015

Usually the analyses of structures are carried out by assuming the base of structures to be fixed. However, the soil beneath foundation alters the earthquake loading and varies the response of structure. Hence, it is not realistic to analyze structures by considering it to be fixed. The importance of soil-structure interaction was realized from the past failures of massive structures by neglecting the effect of soil in seismic analysis. The analysis of massive structures requires soil flexibility to be considered to avoid failure and ensure safety. Present study, considers the seismic behavior of multi-storey reinforced concrete narrow and wide buildings of various heights with and without shear wall supported on raft foundation incorporating the effect of soil flexibility. Analysis of the three dimensional models of six different shear wall positions founded on four different soils has been carried out using finite element software LS DYNA. The study investigates the differences in spectral acceleration coefficient (Sa/g), base shear and storey shear obtained following the seismic provisions of Indian standard code IS: 1893 (2002) (IS) and International building code IBC: 2012 (IBC). The base shear values obtained as per IBC provisions are higher than IS values.

• Journal of Korean Society of Steel Construction
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• v.13 no.3
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• pp.289-299
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• 2001

The purpose of this study was to analyze the characteristics of semi-igid behavior of the steel tubular column to H-beam connection reinforced with exterior square-plate diaphragms and to check the main parameters that affect this behavior. Steel tube connections without interior diaphragm and/or complicated exterior diaphragm show the considerable flexibility due to out of-plane deformation of tube flange. For the exact analysis well-reflected the effect of this flexibility on the overall frame performance. it need to find out the moment-rotation curve function that well trace the result of experiment in the whole region and the function should be simply transformed into an adequate form for the nonlinear analysis program. After collecting several test data same to the connection type considered. we carried out FEM analysis using ANSYS for the assumed beam-to-column connection developed from the simple tension test and the results are compared with experimental values. Based on the parametric study. we proposed the moment-relation curve function and performed the multiple-regression analysis procedure for three parameters consisting of this function with the main geometric parameter of this connection type.

• Journal of the Korean Geotechnical Society
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• v.15 no.3
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• pp.113-129
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• 1999

In this study, a total of 12 types of sequential model tests were conducted at the laboratory for small scale anchored walls. The sequential behavior for flexible wall embedded in sand was investigated by varying degrees of relative density of Joomoonjin sand and flexibility number of model wall. The model tests were carried out in a 1000mm width, 1500mm length, and 1000mm high steel box. Load cells, pressure cells, displacement transducer and dial gauges were used to measure the anchor forces, lateral wall deflections, lateral earth pressures and vertical displacements of ground surface, respectively. Limited model tests were performed to examine the parameters for soil-wall interaction model and the formulation of analytical method was revised in order to predict the behavior of anchored wall in sand. Based on the model tests and proposed analytical method, model simulations were performed and the predictions by the present approach were compared with measurements by the model tests and predictions by other commercial programs. It is shown that the prediction by the present approach simulates qualitatively well the general trend observed for model test.

• Knowledge Management Research
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• v.13 no.3
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• pp.105-125
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• 2012

Previous studies have focused on individual and organizational learning. Amid an increasingly complex business environment, a team system designed to improve flexibility and adaptability constitutes the most basic part of an organization. Still, team learning has rarely been discussed. In addition, team learning behavior, despite being an important part of a team process, is often mentioned as a team-level outcome variable. Given that team learning behavior involves constant changes in thinking and behavior, a shared belief among team members is needed in order to positively influence innovative performance of a team. In spite of that, there has been only limited discussion of it. Besides, few domestic studies have dealt with R&D teams that can clearly demonstrate team learning behavior and team innovative performance. This study is an empirical analysis of the impact of team efficacy on team innovative performance and the mediating role of team learning behavior based on materials collected from team leaders and their immediate subordinates in 268 R&D teams. The analysis showed that team learning behavior actually has a positive effect on team innovative performance. Team efficacy also turned out to have a positive influence on team learning behavior. Lastly, the study found that team learning behavior played a mediating role in the relationship between team efficacy and team innovative performance. Based on those results, the study has identified implications and suggested directions for future research.