• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.1
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• pp.55-68
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• 2007

The purpose of this study was to analyze the distribution of stress in the surrounding bone around implant placed in the first and second molar region. Two different three-dimensional finite element model were designed according to vertical bone level around fixture ($4.0mm{\times}11.5mm$) on the second molar region. A mandibular segment containing two implant-abutments and a two-unit bridge system was molded as a cancellous core surrounded by a 2mm cortical layer. The mesial and distal section planes of the model were not covered by cortical bone and were constrained in all directions at the nodes. Two vertical loads and oblique loads of 200 N were applied at the center of occlusal surface (load A) or at a position of 2mm apart buccally from the center (load B). Von-Mises stresses were analyzed in the supporting bone. The results were as follows; 1. With the vertical load at the center of occlusal surface, the stress pattern on the cortical and cancellous bones around the implant on model 1 and 2 was changed, while the stress pattern on the cancellous bone with oblique load was not. 2. With the vertical load at the center of occlusal surface, the maximum von-Mises stress appeared in the outer distal side of the cortical bone on Model 1 and 2, while the maximum von-Mises stress appeared in the distal and lingual distal side of the cortical bone with oblique load. 3. With the vertical load at a position of 2 mm apart buccally from the center, there was the distribution of stress on the upper portion of the implant-bone interface and the cortical bone except for the cancellous bone, while there was a distribution of stress on the cancellous bones at the apical and lingual sides around the fixture and on the cortical bone with oblique load. 4. With the changes of the supporting bone on the second molar area, the stress pattern on the upper part of the cortical bone between two implants was changed, while the stress pattern on the cancellous bone was not. The results of this study suggest that establishing the optimum occlusal contact considering the direction and position of the load from the standpoint of stress distribution of surrounding bone will be clinically useful.

• Korean Journal of Applied Biomechanics
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• v.29 no.3
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• pp.137-143
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• 2019

Objective: Ligament laxity and hypotonia are characteristics of Down syndrome patients. The aim of this study was to compare the landing pattern between Down syndrome patients and typically developing subjects. To compare the landing pattern, variables related to ligament laxity and hypotonia i.e. vertical stiffness and lower extremities kinematics were investigated. Method: Five subjects with Down syndrome (age: $14.6{\pm}1.8years$, mass: $47.6{\pm}6.94kg$, height: $147.9{\pm}6.0cm$) and six able-bodied subjects (age: $13.2{\pm}0.4years$, mass: $54.7{\pm}6.7kg$, height: $160.1{\pm}9.8cm$) participated in this study. Results: The vertical displacement of the center of mass, vertical reaction force, leg stiffness and range of ankle angle range among Down syndrome patients were significantly different than typically developing group. The youth with Down's syndrome appeared to receive greater vertical impact force at landing than normal youth. Conclusion: The differences in the biomechanical characteristics suggest the delay in motor development among Down syndrome patients and an increased risk of injury to the lower extremity during movement execution such as drop landing.

• Journal of the Korean Society of Costume
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• v.52 no.2
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• pp.31-44
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• 2002

This study was intended to inquire into Check Pattern. The purpose of this study attempted to make a systematic investigation of the characteristic of the Check Pattern, the checker using vertical and horizontal lines which was the universal plastic element and inquire into it in terms of era, designers and combined work. By doing so, this study attempted to Investigate the phase of the Check Pattern in world fashion and further forecast the future of checker design applicable to the 21th century fashion. The result can be summarized as follows : 1. Mondrim's neo-plasticism has not only had a great influence on Op Art and Minimalism work but is deeply related to fashion and textile design. Mondrian used vertical and horizontal line ad the dualistic element. 2. The checker is estimated to have been used since the Etruian times, though uncertain. and largely divided into the Madras check and Scotland Check. Though the origin of the tartan representation of the Scotland check can not be accurately found out, it began to emerge in around the 13th century. 3. Check Pattern has began to be widely used with the development of the textile industry since 1826 and been used in every typical Sihoutto appearing in each era up to the present. And Check Pattern is used most designer in the world, who represent their own personality in their works. This study could find out that the checker is the element of Infinite applicability in the future. It is expected that the sophisticated and beautiful design using the chocker will be presented by many korean designer though the overall and systematic study of the checker.

• Journal of Dental Rehabilitation and Applied Science
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• v.21 no.2
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• pp.169-182
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• 2005

The purpose of this study was to compare the stress distribution around the surrounding bone according to the splinted and non-splinted conditions on the finite element models of the two implant crowns with the different vertical bone level. The finite element model was designed with the parallel placement of the two fixtures ($4.0mm{\times}11.5mm$) with reverse buttress thread on the mandibular 1st and 2nd molars. As the bone quality, the inner cancellous bone and the outer 2 mm cortical bone were designed, and the cortical and cancellous bone were assumed to be perfectly bonded to the implant fixture. The splinted model(Model 1) had 2 mm contact surface and the non-splinted model(Model 2) had $8{\mu}m$ gap between two implant crowns. Two group (Splinted and non-splinted) was loaded with 200 N magnitude in the vertical and oblique directions on the loading point position on the central position of the crown, the 2 mm and 4 mm buccal offset point from the central position. Von Mises stress value was recorded and compared in the fixture-bone interface in the bucco-lingual and mesio-distal sections. The results were as follows; 1. In the vertical loading condition of central position, the stress was distributed on the cortical bone and the cancellous bone around the thread of the fixture in the splinted and non-splinted models. In the oblique loading condition, the stress was concentrated toward the cortical bone of the fixture neck, and the neck portion of 2nd molar in the non-splinted model was concentrated higher than that of 1st molar compared to the splinted model. 2. In the 2 mm buccal offset position of the vertical loading compared to the central vertical loading, stress pattern was shifted from apical third portion of the fixture to upper third portion of that. In the oblique loading condition, the stress was distributed over the fixture-bone interface. 3. In the 4 mm buccal offset position of the vertical loading, stress pattern was concentrated on the cortical bone around the buccal side of the fixture thread and shifted from apical third portion of the fixture to upper third portion of that in the splinted and non-splinted models. In the oblique loading, stresses pattern was distributed to the outer position of the neck portion of the fixture thread on the mesio-distal section in the splinted and non-splinted models. Above the results, it was concluded that the direction of loading condition was a key factor to effect the pattern and magnitude of stress over the surrounding bone of the fixture under the vertical and oblique loading conditions, although the type with or without proximal contact did not effect to the stress distribution.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.6
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• pp.814-822
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• 1986

Flow patterns and its transitions in vertical two phase flow of air-water isothermal flow are identified objectively by void output signals and moments computed from the Probability Density Function which is associated with the statistical measurement for time average local void fractions using conductance probe. It has been shown that the probe output signals, PDF distributions and its moments are deterministic criteria of flow pattern and transition classification.

• Journal of Dental Rehabilitation and Applied Science
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• v.18 no.4
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• pp.301-311
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• 2002

The purpose of this study was to compare the distributing pattern of stress on the finite element models with the different vertical bone level of implant fixture. The two kinds of finite element models were designed according to vertical bone level around fixture ($4.0mm{\times}11.5mm$). The cemented crowns for mandibular first and second molars were made. Three- dimensional finite element model was created with the components of the implant and surrounding bone. Vertical loads were applied with force of 200N distributed within 0.5mm radius circle from the center of central fossa and distance 2mm and 4 mm apart from the center of central fossa. Von-Mises stresses were recorded and compared in the supporting bone, fixtures, abutment screws, and crown. The results were as following : (1) In vertical loading at the center circle of central fossa on model 1 and 2, the difference from vertical bone in implant placement did not affect the stress pattern on all components of implant except for crown. (2) With offset distance incerasing and the bone level of implant decreasing, the concentration of stress occured in the buccal side of long crown, around the buccal crestal bone, and on the fixture- abutment interface. As a conclusion, the research showed a tendency to increase the stress on the supporting bone, fixture and screw under the offset loads when the vertical level of bone around fixture was different. Since the same vertical bone bed has more benefits than the different bone bed around fixtures, it is important to prepare a same vertical level of bone bed for the success of implants under occlusal loads.

• Journal of the Microelectronics and Packaging Society
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• v.16 no.3
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• pp.45-51
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• 2009

Vertical wet equipment was newly developed in stead of horizontal wet equipment which has been widely used for BGA develop process. We intended to eliminate the collision problem between equipment's transferring rollers and fine circuit patterns, which could be achieved by fixing the BGA panel vertically using jig unit. The process characteristics of vertical wet equipment were evaluated by conducting uniformity evaluation, pattern damage evaluation and defect analysis. The process uniformity of the vertical equipment was measured to be the same level as the uniformity of horizontal equipment. And it was measured that $3{\sim}4{\mu}m$ finer circuit pattern could be processed adopting vertical equipment rather than horizontal equipment.

• Korean Journal of Applied Biomechanics
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• v.34 no.1
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• pp.18-24
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• 2024

Objective: The purpose of this study was to evaluate the effects of an 8-week velocity-based training on the maximum vertical jump in elite sprinters. Method: Ten elite sprinters were participated in this study (age: 21 ± 0.97 yrs., height: 179 ± 3.54 cm, body mass: 72 ± 2.98 kg). An 8-week velocity-based power training was provided to all subjects for twice per week. Their maximum vertical jumps were measured before and after velocity-based training. A 3-dimensional motion analysis with 8 infrared cameras and 4 channels of EMG was performed in this study. A paired t-test was used for statistical verification. The significant level was set at α=.05. Results: There were no statistically significant differences were found between pre and post the training (p>.05). However, most variables included jump record, knee joint ROM, and muscle activation of rectus femoris showed increased pattern after the training. Conclusion: In this study, an 8-week velocity-based training did not showed the significant training effects. However, knee joint movement which is the key role of the vertical jump revealed positive kinematic and kinetic pattern after the training. From this founding, it is believed that velocity-based training seems positively affect the vertical jump which is the clear measurement of mechanical power of sprinter. In addition, to get more clear evidence of the training more training period would be needed.

• International Journal of Costume and Fashion
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• v.5 no.2
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• pp.55-67
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• 2005

The purpose of this study is to document an unidentified velvet fabric which is located in the Museum. The investigation was conducted by analyzing color, weaving technique. pattern of the study object. To identify the origin of the object, many references about color trends, construction methods and patterns were accessed. Two comparative objects which were dating from 1600 to 1699 in the Museum of F.I.T. were selected since they are similar to the study object. The results of this study can be summarized as follows; (1) The type of this study object is 'cut and voided velvet'. It is obtained establishing the motif as areas of cut pile so as to form a pattern, while leaving other areas of the grounded weave without pile. Two flowers and two tulips with S curved stems are composed as one unit in the vertical direction. (2) The colors used in this study object. which are ivory, smoke blue, medium orange, and yellow. are part of a new trend color in the $17^{th}$ century. (3) The vertical undulating stripe patterns are also of significance in this fabric. They seemed to be contemporary with the serpentine line which was common since the $15^{th}$ century and the vertical stripes pattern which appeared from the $16^{th}$ century. (4) The stylized tulip patterns of this study object began to appear in the early $17^{th}$ century. The stems and leaves of this patterns are less sinuous than the floral motifs of the later $17^{th}$ century. Therefore, the study object is dated to early in $17^{th}$ century because of the color combination. stripes. stylized tulips, leaves. and stems are showing the characteristics of this period.

• The korean journal of orthodontics
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• v.51 no.3
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• pp.166-178
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• 2021

Objective: To investigate dimensional changes in regional pharyngeal airway spaces after premolar extraction in bimaxillary skeletal protrusion (BSP) patients according to vertical skeletal pattern, and to further identify dentoskeletal risk factors to predict posttreatment pharyngeal changes. Methods: Fifty-five adults showing BSP treated with microimplant anchorage after four premolar extractions were included in this retrospective study. The subjects were divided into two groups according to the mandibular plane steepness: hyperdivergent (Frankfort horizontal plane to mandibular plane [FH-MP] ≥ 30) and nonhyperdivergent groups (FH-MP < 30). The control group consisted of 20 untreated adults with skeletal Class I normodivergent pattern and favorable profile. Treatment changes in cephalometric variables were evaluated and compared. The association between posttreatment changes in the dentoskeletal and upper airway variables were analyzed using linear regression analysis. Results: The BSP patients showed no significant decrease in the pharyngeal dimensions to the lower level in comparison with controls, except for middle airway space (MAS, p < 0.01). The upper airway variable representing greater decrease in the hyperdivergent group than in the nonhyperdivergent group was the MAS (p < 0.01). Posttreatment changes in FH-MP had negative correlation with changes in MAS (β = -0.42, p < 0.01) and inferior airway space (β = -0.52, p < 0.01) as a result of multivariable regression analysis adjusted for sagittal skeletal relationship. Conclusions: Decreased pharyngeal dimensions after treatment in BSP patients showed no significant difference from the normal range of pharyngeal dimensions. However, the glossopharyngeal airway space may be susceptible to treatment when vertical dimension increased in hyperdivergent BSP patients.