• The Journal of Korean Academy of Prosthodontics
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• v.55 no.2
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• pp.187-197
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• 2017

Deep overbite patients who do not have proper occlusal relationship may cause problems such as teeth wear and antagonist extrusion. These lead to the collapse of occlusal plane and esthetic problem. Increasing vertical dimension is frequently essential to resolve those problems. This case report demonstrates a full-mouth rehabilitation for a patient with severe deep bite that contacts surface to surface by increasing vertical dimension. Treatment procedures included diagnosis, treatment planning, implant surgery, and prosthodontic rehabilitation. Satisfactory results were obtained in functional and esthetic aspects.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.3
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• pp.207-215
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• 2017

Many factors should be considered for successful denture treatment at edentulous patients: support, retention, stability, occlusion, esthetics, etc. The patient who has severely absorbed residual ridges, however, treatments are challenging to satisfy those factors. The dentures that use anatomic artificial teeth show good mastication efficiency and esthetics but, can easily lose stability at absorbed ridges. On the contrary, the dentures that use non-anatomic artificial teeth perform better stability but, lower masticatory efficiency and esthetics at absorbed ridges. The lingualized occlusion, using both anatomic and non-anatomic teeth, introduced for compromise those of the pros and cons. At lingualized occlusion, buccal cusps of the teeth do not contact on centric relation. Therefore, direction of the occlusal force towards lingually, then stability of dentures increases. This case report shows the results of the treatment flat residual ridges using complete dentures with ligualized occlusion to increase dentures stability and satisfactory of the patient.

• Tribology and Lubricants
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• v.38 no.3
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• pp.73-83
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• 2022

This paper is concerned with an analysis of a surface edge crack emanated from a sharp contact edge. For a geometrical model, a square wedge is in contact with a half plane whose materials are identical, and a surface perpendicular crack initiated from the contact edge exists in the half plane. To analyze this crack problem, it is necessary to evaluate the stress field on the crack line which are induced by the contact tractions and pseudo-dislocations that simulate the crack, using the Bueckner principle. In this Part I, the stress filed in the half plane due to the contact is re-summarized using an asymptotic analysis method, which has been published before by the author. Further focus is given to the stress field in the half plane due to a pseudo-edge dislocation, which will provide a stress solution due to a crack (i.e. a continuous distribution of edge dislocations) later, using the Burgers vector. Essential result of the present work is the corrective functions which modify the stress field of an infinite domain to apply for the present one which has free surfaces, and thus the infiniteness is no longer preserved. Numerical methods and coordinate normalization are used, which was developed for an edge crack problem, using the Gauss-Jacobi integration formula. The convergence of the corrective functions are investigated here. Features of the corrective functions and their application to a crack problem will be given in Part II.

• Journal of Astronomy and Space Sciences
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• v.22 no.3
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• pp.223-232
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• 2005

New BVR CCD light curves of the low mass ratio contact binaries, V410 Aur and V776 Cas, were observed with the 61 cm reflector and a 2K CCD camera at the Sobaeksan Astronomical Observatory. The absolute dimensions of the low mass ratio contact binaries, V410 Aur and V776 Cas, were obtained using WD program from the published spectroscopic and newly observed photometric data. The evolutionary status of this type of binary system including V410 Aur and V776 Cas has been considered. We reconfirmed that the primary stars of the low mass contact binary system were located on the TAMS and secondary stars were located under the ZAMS in H-R diagram.

• Journal of the Korean Geotechnical Society
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• v.19 no.5
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• pp.223-232
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• 2003

In this study, a constitutive model called the disturbed state concept (DSC) was modified to be applied to the interface shear stress-displacement relationship between geosynthetics. The DSC model is comprised of two reference states, namely the relative intact (RI) and the fully adjusted (FA) state, and one function, namely the disturbance function. This model is a unified approach and can allow for various models as an RI state such as elastic-perfectly plastic model, hierarchical model, and so on. In addition, by using this model, the elastic and plastic displacements can be considered simultaneously. Comparisons between the measured data and predicted results through the parameters determined from four sets of large direct shear tests showed good agreements with each other, especially for the smooth geomembrane-involved interface. Although there are slight differences at peak shear strength for textured geomembrane-involved interface, this model can still be useful to predict the position of displacement at peak strength and the large displacement (or residual) shear strength.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.6
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• pp.569-577
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• 2010

A multiscale particle simulation technique that can be applied to a multiphase fluid system has been developed. In the boundary region where the macroscopic- and microscopic-scale models overlap each other, three distinctive features are introduced in the simulation. First, a wall is set up between the gas and liquid phases to separate them and match the phases respectively to the macroscopic conditions stably. Secondly, the interfacial profile is obtained near the matching region and the wall translates and rotates to accommodate the change in the liquid-vapor interfacial position in the molecular model. The contact angle thus obtained can be sent to the macroscopic model. Finally, a state of mass and temperature in the region is maintained by inserting and deleting the particles. Good matching results are observed in the cases of the complete and partial wetting fluid systems.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.11
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• pp.7-14
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• 2005

A subdomain-interface finite element method is suggested to solve a class of fully- coupled thermomechanical problems with contact boundaries. The penalty method is used for connecting subdomains that satisfy interface compatibility conditions. As a result, effective stiffness matrices are always positive definite, and computational efficiency can be improved to a considerable degree. Moreover, any complex-shaped domain can be divided into independently modeled subdomains without considering the conformity of meshes on interfaces. Using a computer code based on the present method, these advantageous features are shown through a set of numerical studies.

• Clean Technology
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• v.20 no.4
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• pp.354-358
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• 2014

Ionic liquid (IL) is a salt presents in a liquid form at room temperature. Recently, it attracts huge attention due to its possibilities as a clean solvent, electrolyte, and catalyst. In the present work, the charging behavior of six different ILs were investigated using droplet contact charging phenomenon in a dielectric medium. Basically, the charging of an IL droplet can be explained by a perfect conductor theory. However, there were several different features depending on the species of ions of ILs, which requires rigorous molecular level modeling of charge transport through electrochemical reaction of IL. We hope the present results contribute to build up fundamental understanding of electrochemical charge transport of IL.

• Journal of the Korean Magnetics Society
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• v.9 no.1
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• pp.48-54
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• 1999

For the high speed linear motor and the transportation device at clean room, a magnetic levitation rail without contact using the repulsive force of permanent magnets was newly developed. The characteristics of repulsive and lateral forces of the magnetic levitating system using permanent magnet was studied and the devised magnetic levitating system was evaluated by analytical and experimental approaches. This system is composed of two fixed guide rails with the rare earth permanent magnet array and a moving unit which is attached two magnet pairs at each sides. Because this system was forcedly levitated by the face to face repulsive forces, levitating air gap length can be repulsive force of an auxiliary magnetic repulsion system on the center of moving unit.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.1
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• pp.37-44
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• 2019

A bond-based peridynamic model has been reported dynamic fracture characteristic of brittle materials through a simple constitutive model. In the model, each bond is assumed to be a simple spring operating independently. As a result, this simple bond interaction modeling restricts the material behavior having a fixed Poisson's ratio of 1/4 and not being capable of expressing shear deformation. We consider a state-based peridynamics as a generalized peridynamic model. Constitutive models in the state-based peridynamics are corresponding to those in continuum theory. In state-based peridynamics, thus, the response of a material particle depends collectively on deformation of all bonds connected to other particles. So, a state-based peridynamic theory can represent the volume and shear changes of the material. In this paper, the perfect plasticity is considered to express plastic deformation of material by the state-based peridynamic constitutive model with perfect plastic flow rule. The elastic-plastic behavior of the material is verified through the stress-strain curves of the flat plate example. Furthermore, we simulate the high-speed impact on 3D granite model with a nonlocal contact modeling. It is observed that the damage patterns obtained by peridynamics are similar to experimental observations.