• Journal of Industrial Technology
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• v.24 no.B
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• pp.95-105
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• 2004

This paper is an experimental and numerical research works about the effects of the b earing capacity of sloped rubble mound on the density of rubble mound and the position of footing. Centrifuge model tests were performed to investigate the bearing capacity of rubble m ound by changing the density of rubble mound and the location of loading in forms of s trip loading to simulate the caisson. Materials of rubble mound used in the model tests were crushed rocks having similar value of uniformity coefficient to the value in field. Two different relative densities of 80% and 90% were prepared during tests. The dimens ions of centrifuge model were trapezoidal shape of model mound having the bottom wid th of mound, 30cm and height of mound, 10cm. Gravity level applied during the centrif uge test was 50G. Surcharge loading in the forms of strip loading was applied on the t op of the sloped model mound. Tests were carried out by changing the position of loadi ng. The rigid model footing was located in the center of top of the model rubble mound and the edge of model footing was at the crest of mound. Test results were analyzed by using the limit equilibrium methods proposed by Meyer hof(1957) and Bowles(1982) and the numerical approach with FLAC being available com mercially software. For the numerical estimations with FLAC, the rubble mound was si mulated with the constitutive relationship of Mohr-Coulomb elasto-plastic model.

• Geotechnical Engineering
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• v.11 no.3
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• pp.81-90
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• 1995

Based on the close investigation of Lade elasto -plastic model, this study proposes a new elasto -plastic constitutive model for foundation composed of granular soils. The new model contains 1st stress invariant in plastic potential function as well as yield function, which is different from Lade original model. Both these functions called a correction function include a correction term. To validate the new analytical model, it was compered with some previous models. Comparison between the test results and numerical results using Lade and new model was carried out concerning Sacramento River sand, U.S.A and Backma River sand. The conclusion was obtained that more refined model well be deft.eloped throughout this research.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.6
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• pp.623-630
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• 2013

This study was to evaluate hydrodynamic performance evaluation between an abroad product, a developed inflatable kayak and new developed kayaks. In order to test, inclining and turning trial test were carried out in the Ocean engineering Basin. Also, resistance test was carried out using a reduced scale model in the circulating water channel. In conclusion, stability of KONA was evaluated was the most greatest, the coefficient of resistance and center of gravity from RD-FK-12 were considerable, and turning performance of RD-FK-11 was greater than this of KONA and RD-FK-12.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.2
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• pp.253-265
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• 1993

This paper presents a numerical method for implementing a nonlinear constitutive material model developed by Lade, into a finite element computer program. The techniques used are based on the displacement method for the solution of axial symmetric and plane strain nonlinear boundary value problems. Laboratory behaviour of Baekma river sand(#40-60) is used to illustrate the determination of the parameters and verification of the model. Computer procedure is developed to determine the material parameters for the nonlinear model from the raw laboratory test data. The model is verified by comparing its predictions with observed data used for the determination of the parameters and then with observed data not used for the determination. Three categories of tests are carried out in the back-prediction exercise; (1) A hydrostatic test including loading and unloading response, (2) Conventional triaxial drained compression tests at three different confining pressure and (3) A model strip footing test not including in the evaluation of material parameters. Pertinent observations are discussed based on the comparison of predicted response and experimental data.

• Journal of KIISE:Software and Applications
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• v.33 no.1
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• pp.44-57
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• 2006

With the rapid growth of network technology, two or more products from different vendors are integrated and interact with each other to perform a certain function in the latest systems. Thus. interoperability testing is considered as an essential aspect of correctness of integrated systems. Interoperability testing is to test the ability of software and hardware on different machines from different vendors to share data. Most of the researches model communication system behavior using EFSM(Extended Finite State Machines) and use EFSM as an input of test scenario generation algorithm. Actually, there are many studies on systematic and optimal test case generation algorithms using EFSM. But in these researches, the study for generating EFSM model which is a foundation of test scenario generation isn't sufficient. This study proposes an EFSM generating technique from informal requirement analysis document for more complete interoperability testing. and implements prototype of Test Case Generation Tool generating test cases semi-automatically. Also we describe theoretical base and algorithms applied to prototype implementation.

• Sleep Medicine and Psychophysiology
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• v.16 no.1
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• pp.5-9
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• 2009

Relatively little is known about the neurobiology of insomnia, despite its wide prevalence and broad medical impact. Although much is still to be learned about the pathophysiology of the disorder, identification, systematic assessment, and appropriate treatment are clearly beneficial to patients. Recent research, using quantitative EEG, polysomnography (PSG), multiple sleep latency test (MSLT) and neuroimaging techniques, suggests that some broad areas can be identified as possible pathophysiological models. Sleep-wake homeostat model hypothesizes a failure in homeostatic regulation of sleep, an attenuated increase in sleep drive with time awake, and/or defective sensing of sleep need. Circadian clock model hypothesizes a dysfunctional circadian clock, resulting in changes in the timing of sleep-wake propensity that are incompatible with normal sleep. Intrinsic sleep-wake state mechanism model suggests that abnormal function of insomnia comprises the systems responsible for expression of the sleep states themselves. Extrinsic over-ride mechanism (stress-response) model suggests that insomnia reflects the consequences of overactivity of one of the systems considered "extrinsic" to normal sleep-wake control. Many current therapies for insomnia are based on these physiological models. Several attempts have been made to create a physiological model that would explain this disorder and could be used as a foundation for treatment. However, it appeared that no model can fully explain and clarify all aspects of insomnia. Future research should be necessary to expand our knowledge on the biological dimensions of insomnia.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.1106-1116
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• 2008

Single-pole transmission structures which are supported by drilled shaft foundations are usually subjected to large overturning moments with modest vertical and lateral loads. To analyze the behavior of the drilled shaft under such loading conditions, an analytical model was developed based on beam-column and subgrade reaction methods. Field model tests were performed to calibrate the developed analytical model in which additional subgrade spring models were adopted. The field test results estimated from the calibrated analytical model were compared with those calculated by one spring model and other commercial program. According to the comparison study, the developed analytical model was proven to be a useful tool to analyze the laterally loaded behavior of foundations for single-pole structures.

• The Journal of Korean Physical Therapy
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• v.33 no.5
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• pp.224-230
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• 2021

Purpose: The purpose of this study was to investigate the effects of the fascia distortion model (FDM), one of the fascia treatments, on unstable ankle subjects. This was done through the chronic ankle instability tool (CAIT) questionnaire on maximum isometric muscle strength, proprioception, dynamic balance, and maximum angle. Methods: An experiment was conducted using the chronic ankle instability tool questionnaire on males and females in their twenties who suffered from ankle instability. Before the experiment, maximum isometric strength, proprioceptive, dynamic balance, and maximum angle were measured. The fascia distortion model was applied and then measurements were taken again to compare and analyze the changes. Analysis was carried out using the paired t-test. Results: After applying the fascia distortion model, maximum isometric strength, proprioceptive, dynamic balance, and maximum angle significantly improved (p<0.05). Conclusion: This study found that the fascia distortion model method was effective in improving maximum isometric strength, proprioceptive, dynamic balance, and maximum angle. The results suggest that the fascia distortion model method is a new intervention that could be used for subjects with chronic ankle instability.

• Journal of Ocean Engineering and Technology
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• v.28 no.2
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• pp.133-139
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• 2014

Offshore wind turbines have been constructed extensively throughout the world. These turbines are subjected to approximately $10^8$ horizontal load cycles produced from wind, waves, and current during their lifetimes. Therefore, the accumulated displacement of the foundation under horizontal cyclic loading has significant effects on the foundation design of a wind turbine. Akili(2006) and Achmus et al.(2009) performed cyclic triaxial tests on dry sands and proposed an empirical model for predicting the accumulated plastic strain of sands under long-term cyclic loading. In this study, cyclic triaxial tests were performed to analyze the cyclic loading behaviors of dry sands. A total of 27 test cases were performed by varying three parameters: the relative density of the sands, cyclic load level, and confining stress. The test results showed that the accumulated plastic strain increased with an increase in the cyclic load level and a decrease in the relative density of the sand. The confining stress had less effect on the plastic strain. In addition, the plastic strain at the 1st loading cycle was about 57% of the accumulated strain at 1,000 cycles. Finally, the input parameters of the empirical models of Akili(2006) and Achmus et al.(2009) were evaluated by using the relative density of the sand and the cyclic load level.

• Earthquakes and Structures
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• v.17 no.6
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• pp.635-647
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• 2019

Tests and theoretical studies for seismic responses of a transmission tower-line system under coupled horizontal and tilt (CHT) ground motion were conducted. The method of obtaining the tilt component from seismic motion was based on comparisons from the Fourier spectrum of uncorrected seismic waves. The collected data were then applied in testing and theoretical analysis. Taking an actual transmission tower-line system as the prototype, shaking table tests of the scale model of a single transmission tower and towers-line systems under horizontal, tilt, and CHT ground motions were carried out. Dynamic equations under CHT ground motion were also derived. The additional P-∆ effect caused by tilt motion was considered as an equivalent horizontal lateral force, and it was added into the equations as the excitation. Test results were compared with the theoretical analysis and indicated some useful conclusions. First, the shaking table test results are consistent with the theoretical analysis from improved dynamic equations and proved its correctness. Second, the tilt component of ground motion has great influence on the seismic response of the transmission tower-line system, and the additional P-∆effect caused by the foundation tilt, not only increases the seismic response of the transmission tower-line system, but also leads to a remarkable asymmetric displacement effect. Third, for the tower-line system, transmission lines under ground motion weaken the horizontal displacement and acceleration responses of transmission towers. This weakening effect of transmission lines to the main structure, however, will be decreased with consideration of tilt component.