• Transactions of Materials Processing
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• v.31 no.4
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• pp.200-206
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• 2022

The finite element analysis is one of the representative methods for predicting the materials behavior for experiments that are difficult to perform empirically. Constitutive equations are essential for reducing computation time and sharing data because they enable finite element analysis simulations through simple formulae. However, it is difficult to derive accurate flow curves for all materials as most constitutive equations are not formulated based on their physical meaning. Also, even if the constitutive equation is a good representation of the flow curve to the experimental results, some fundamental issues remain unresolved, such as the effect of mesh size on the calculation results. In this study, a new constitutive equation was proposed to predict various materials by modifying the combined Swift-Voce model, and the calculation results with various mesh sizes were compared to better simulate the experimental results.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.3
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• pp.133-141
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• 2007

A finite element model is developed for the extended Boussinesq equations that is capable of simulating the dynamics of long and short waves. Galerkin weighted residual method and the introduction of auxiliary variables for 3rd spatial derivative terms in the governing equations are used for the model development. The Adams-Bashforth-Moulton Predictor Corrector scheme is used as a time integration scheme for the extended Boussinesq finite element model so that the truncation error would not produce any non-physical dispersion or dissipation. This developed model is applied to the problems of solitary wave propagation. Predicted results is compared to available analytical solutions and laboratory measurements. A good agreement is observed.

• The Journal of Information Technology
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• v.10 no.2
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• pp.37-45
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• 2007

The multiple-ability which the structure and the physical properties which the carbon or scull tube are unique show the applicability is superior in the plane indication element which is an indispensability of information communications apparatus, the stubbornness memory element, 2nd change of air and the rough copy dosage [khay] plaque seater, the hydrogen store material and the chemical sensor back and it has the possibility which will pass over the limit which the element of existing has. from the present paper it compared in the steel and only 10 the boat it did and it analyzed against an energy storage space voluntary application and developmental apply the carbon or scull tube trend in order about under researching the effective energy storage element it could be appeared, the technique of the strong carbon nano tube. 1. The hazard which embodies the energy storage element which uses the carbon or scull tube it follows in the function which stands and CNT of the structure which is various is necessary. 2. CNT fabrications of each one must precede possible not only must be each Cabinet conference circumstances quality gain and loss. 3. The structural control of syntheses, length controls, diameter controls and the metal - CNT junction control backs of quality CNT must precede. Applies the hereafter carbon or the scull tube in the various element with the primary preceding base technique for the structural plan technique of the carbon or scull tube to be certainly established, it does, secondarily the various element functional control technique which uses the carbon or scull tube is researched and will do.

• Korean Journal of Health Education and Promotion
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• v.13 no.1
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• pp.117-127
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• 1996

The purpose of this study was to investigate the variation in constituent element of blood between the massage group and non-massage group for period of convalescence after giving intense physical exercise of 180beat/min. for 10 men studying physical exercises. Education in K university served as the subjects for this study. The following are the results of the study. 1. The variation in white blood corpuscles showed a tendency of equal ascension in both groups just after finishing physical exercise, but the subjects in the massage group showed quicker recuperation than the subjects in the non-massage. The subjects in the massage group showed a lower tendency than the subjects in the non-massage group for 30minutes after finishing physical exercise. 2. In the variation of red blood corpuscles, it was increased in the massage and non-massage group after physical exercise, but it showed a tendency to drastically decrease in the massage group after 30 minutes. 3. Hemoglobin showed a variation increasing in the massage group and non-massage group after physical exercise, but it showed a tendency of rapid decrease in the massage group after 30 minutes. 4. In the variation of hematocrit, it showed a tendency of similar increase after physical exercise in the massage and non-massage group, but the subjects in the massage group showed a higher decrease than ones in the non-massage after 30 minutes. 5. Blood platelet was increased in the subjects of the massage group after physical exercise, but it was decreased drastically after 30 minutes. 6. In the variation of blood glucose, it was increased in the subjects in the massage group and decreased in the non-massage group after physical exercise, but it showed a tendency of rapid decrease in the non-massage group after 30 minutes.

• Korean Journal of Clinical Laboratory Science
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• v.36 no.2
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• pp.252-257
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• 2004

The purpose of this study was to investigate the variation in constituent element of blood between the massage group and non-massage group in the period of convalescence after giving intense physical exercise for ten T'ae-Kwondo martial artists. In the variations of red blood cells, white blood cells, hematocrit, hemoglobin and blood platelet, levels decreased during the rest time after physical exercise, but the subjects in the massage group showed lower tendency than the subjects in the non-massage group after physical exercise. The variation of calcium showed an ascension tendency in the massage group after physical exercise. Creatine phosphokinase was increased after physical exercise, but it showed a tendency of rapid decrease in the massage group. Lactic acid showed a variation increase after physical exercise. It showed a tendency of decrease during the rest time in the non-massage group, but it was increased after sports massage. The variation of blood glucose was increased after physical exercise. It was maintained in the massage group after physical exercise in contrast to the non-massage group whose levels decreased during the rest time.

• Convergence Security Journal
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• v.15 no.7
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• pp.63-68
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• 2015

In rapid aging society, the disease prevention and management for healthy life of the elderly is very important. Regular physical activity is known to be a useful intervention for the physical and mental health of the elderly. In this study, we explore the convergence contents using IT technology as the intervention for encouraging the regular physical activity in the elderly. There are u-Healthcare and serious game as the convergence of health care and IT technology, and the serious game which is added special purpose such as education, training, and treatment to the fun-one of the game element- can be suitable to provide a variety of contents that leads to physical activity in the elderly. The contents inducing physical activities are "Puffer(ATARI, USA)", "WiiFit(Nintendo, JAPAN)", "Age Invaders(MXR Lab, SINGAPORE)", "Xbox $360^{\circ}$+kinect(Microsoft, USA)", "Tangible bicycle game(Donsin Univ., KOREA)", and "3D Gateball game(Soongsil Univ., KOREA)", and these contents can help health care of the elderly. By increasing physical activity through the use of these contents, it will be able to promote physical fitness and body function required in daily life, disease prevention, and maintain health in the elderly.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2409-2421
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• 2011

This paper will present hybrid tests to a one bay-one story steel frame structure under ground excitation. A structure used in this paper for hybrid test, to evaluate performance and behavior, is divided into two models; one is numerical model with one column element, and a truss or a beam element, the other is physical substructural model with one beam-column element. All tests considered one or three degrees of freedom to implement real-time hybrid test, and two control algorithms to control hardware are used; one using MATLAB/Simulink, the other using OpenSees, OpenFresco and xPCTarget. In addition, for real-time data communication between numerical and physical substructural models SCRAMNet was used. The results of hybrid tests were compared with one of numerical analysis of numerical model with fiber force-based beam-column elements using OpenSees. Real-time hybrid tests were implemented for the validation of control system with simple structure, and then it will be extended to hybrid test for higher nonlinear or complex structure later on.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.4
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• pp.323-329
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• 2013

This study attempts to simulate the structure of a woody leaf netted venation system by using topology optimization techniques. Based on finite element method (FEM) analysis of an incompressible fluid, a topology optimal design is applied to those woody leaf netted venation models. To solve the transverse shear locking problem of a thin plate caused by the Mindlin-Reissner plate model where a leaf netted venation is assumed to be a thin plate, a P1-nonconforming element and selective reduced integration are employed. Topology optimal design is applied to multiple physical domains. Combined with the Darcy-Stokes flow problems and extended to the optimal design of fluid channels, the multiple physical models of the flow system are analyzed and venation patterns of leafs are simulated. The calculated optimal shapes are compared with the natural shapes of woody leaf venation patterns. This interdisciplinary approach may improve our understanding of the leaf venation system.

• Elastomers and Composites
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• v.43 no.3
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• pp.173-182
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• 2008

Rubber-pad forming process for materials such as metal in which portions of the die which act upon the material is composed of a natural or synthetic rubber or elastomer material. This makes the rubber pad forming process relatively cheap and flexible, high accuracy for small product series in particular. In this study, we carried out the physical test and finite element analysis of elastomer such as natural rubber and urethane for steel rack rube forming. The non-linear property of elastomer which are described as strain energy function are important parameter to design and evaluate of elastomer component. These are determined by material tests which are uni-axial tension and bi-axial tension. This study is concerned with simulation and investigation of the significant parameters associated with this process.

• Journal of the Korean Geosynthetics Society
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• v.9 no.3
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• pp.39-45
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• 2010

When the ground temperature drops below $0^{\circ}C$, wet soils expand due to the ice formation in their porous space. This results in frost heave which causes structural stability problems. Frost heave is attributed by several factors such as physical soil properties and heat transfer including pore water phase change. Due to the complex physical phenomena, reliable and verified multi-dimensional numerical models for frost heave problems are still in a research stage. This study presents an efficient and simple method of overcoming numerical problems associated with sudden jump of heat capacity due to the phase change from water to ice in the pore space. This paper proposes heat transfer equation and finite element method when the saturated soils or porous rocks are subjected to freezing. Numerical analyses using the proposed method agree well with the known closed form solution and the laboratory test results.