• The Journal of the Korean dental association
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• v.48 no.9
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• pp.670-679
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• 2010

Esthetic demands for dental treatment are increasing every day. The interdisciplinary relationship of the restorative treatment, periodontal therapy and other treatments such as endodontics, orthodontics and so on is more emphasized nowadays to reconstruct the hard and soft tissue foundation for the esthetic restorative treatment. This article will focus on the periodontal plastic surgery for esthetic restorative treatment. These followings will be discussed. 1. Understand the relationship between teeth and gingival scaffold for esthetics 2. Discuss the classification and treatment of gummy smile 3. Recognize the gingival margin irregularities by gingival recession and how to achieve the harmonic soft tissue margins 4. describe the hard and soft tissue augmentation for ridge augmentation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1414-1417
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• 2004

A thick-layered RP process, transfer-type variable lamination manufacturing using expandable polystyrene foam (VLMST) has been developed to have the advantageous characteristics such as high building speed, low cost for introduction and maintenance of VLM-ST apparatus, and little staircase surface irregularities of parts. However, VLM-ST has difficulty fabricating an axisymmetric shape and a large-sized freeform shape because of the limited sloping angles and small build size. The objective of this paper is to develop a multi-functional hotwire cutting system using EPS-foam (MHC). MHC employs a four-axis synchronized hotwire cutter with the structure of two XY movable heads and a turntable. In order to examine the applicability of the developed MHC apparatus, an axisymmetric shape, a polyhedral shape and a large-sized freeform shape were fabricated on the apparatus.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.10a
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• pp.161-168
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• 2006

The recent unpredictable weather condition, especially abnormal heavy precipitation which is on the verge of PMF, made implement more rigorous design standard. Following these trends, the idea of additional auxiliary spillway, most of them are tunnel around existing one, is adopted to many sites. Tunnel spillway, having free water table is generally consisted of several compartments such as inlet, transition, inclined, curved and stilling parts. It may has some technical problems to be considered. Among them, the surface deterioration due to cavitation is reported many times in the part of irregularities on lining. Including this kind of problem, several technical considerations for tunnel spillway will be handled in this paper during design procedure.

• Journal of the Korean Society for Precision Engineering
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• v.9 no.1
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• pp.53-65
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• 1992

For improving the performance of maglev systems with a combined lift and guidance, it is suggested that the multivariable control systems and a secondary suspension should be added. The former is required to reject both track irregularities in vertical disturbances and wind gusts in lateral disturbances, and the latter to guarantee passengers against an unsatisfied criteria in ride quality. In this paper, bond graph model for the study of nonlinear dynamics of maglev systems with a combined lift and guidance is presented briefly. And, the secondary suspension is analyzed to understand the role of stiffness and damping factors in passive devices. Finally, LQG/LTR mulitivariable control systems are designed for the overall maglev systems with and without secondary suspension, and then the system performances in these two cases are evaluated.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.328-333
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• 2002

When vehicle travelling along the track which has irregularity such as vertical profile, dynamic forces arise at the Wheel/Rail contact patch by wheel/rail interaction. In particular short wavelength irregularities on dipped joint and small stiffness of connecting rail bring about intense wheel/rail dynamic effects at higher speed. In the paper, a new model for dipped joint rail is developed to study dynamic behavior of track. A cusp behavior on dipped joint was defined by its amplitude and decay factor, which was presented by FRA track classes. The result of case study are presented, which show wheel rail contact force in each track classes, train operation speed and bending flexible rigidity ratio of fishplates which are connecting the rail.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2445-2452
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• 2012

RNA interference has created a breakthrough in gene silencing technology and there is now much debate on the successful usage of RNAi based methods in treating a number of debilitating diseases. Cancer is often regarded as a result of mutations in genomic DNA resulting in faulty gene expression. The occurrence of cancer can also be influenced by epigenetic irregularities in the chromatin structure which leads to alterations and mutations in DNA resulting in cancer cell formation. A number of therapeutic approaches have been put forth to treat cancer. Anti cancer therapy often involves chemotherapy targeting all the cells in common, whereby both cancer cells as well as normal cells get affected. Hence RNAi technology has potential to be a better therapeutic agent as it is possible to deactivate molecular targets like specific mutant genes. This review highlights the successful use of RNAi inducers against different types of cancer, thereby paving the way for specific therapeutic medicines.

• Proceedings of the KSR Conference
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• 2003.10b
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• pp.182-187
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• 2003

The analysis of mud pumping which causes track irregularities during softening of present roadbed is needed in order to prepare countermeasure that is efficient and reasonable against the softening of railway roadbed. In this study, model tests were performed in order to evaluate property of the railway softening under the train loading, considering the wheel load and the impact coefficient due to the train passing velocity. The existence of the mud pumping, settlements of roadbed and vertical earth pressure were measured under the train loading.

• Structural Engineering and Mechanics
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• v.49 no.3
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• pp.329-353
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• 2014

Increasing usage of tank cars and their intrinsic instability due to sloshing of contents have caused growing maintenance costs as well as more frequent hazards and defects like derailment and fatigue of bogies and axels. Therefore, varieties of passive solutions have been represented to improve dynamical parameters. In this task, assuming 22 degrees of freedom, dynamic analysis of partially filled tank car traveling on a curved track is investigated. In order to consider stochastic geometry of track; irregularities have been derived randomly by Mont Carlo method. More over the fluid tank model with 1 degree of freedom is also presented by equivalent mechanical approach in terms of pendulum. An active suspension system for described car is designed by using linear quadratic optimal control theory to decrease destructive effects of fluid sloshing. Eventually, the performance of the active suspension system has been compared with that of the passive one and a study is carried out on how active suspension may affect the dynamical parameters such as displacements and Nadal's derailment index.

• Korean Journal of Computational Design and Engineering
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• v.2 no.3
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• pp.133-141
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• 1997

In the process of car body design, various surfaces are generated from the given boundary curves. Depending upon the method of the surface generation and the quality of the boundary curves provided, the resulting surfaces may have global or local irregularities in many cases. Thus it would be necessary for the designer to evaluate the surface quality and to modify the surface or to use the different generation method based on the evaluation results. This capability is very important because the defect of the surface quality detected in the production stage will require the rework of the dies and will cause a big loss in cost and time. A method of surface interrogation using reflection line is introduced. In this paper, We applied reflection mapping to generate reflection lines on the trimmed NURBS surface. Since reflection lines are obtained from reflection mapping that uses simple and physically acceptable mapping algorithm, they can be efficiently used to simulate the reflection test on the real part in the production line.

• Journal of Magnetics
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• v.15 no.3
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• pp.99-102
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• 2010

We present the fractal properties of the magnetic domain walls in $(5-{\AA}\;Co_{90}Fe_{10}/10-{\AA}\;Pt)_n$ multilayer films with perpendicular magnetic anisotropy for the number of repeats n (1 to 5). In these films, the magnetization reversed due to the domain wall propagation throughout the films with rare nucleations. As n increased, it was observed that the jaggedness of the domain walls increased noticeably, which is possibly due to the accumulation of irregularities at the layer interfaces. The jaggedness of the domain walls was analyzed in terms of the fractal dimension by use of the ruler method, and it was revealed that the fractal dimension significantly changed from $1.0{\pm}0.002$ to $1.3{\pm}0.05$ as n increased from 1 to 5.