• Journal of the Ergonomics Society of Korea
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• v.18 no.1
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• pp.91-108
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• 1999

In our previous work using a motion analyzer and 3-dimensional sonic digitizer, the arm shapes for 23 women in their early twenties were classified into three characteristic types. In order to design sleeves, suitable for arm movements for the three characteristic arm shapes, a relationship between arm length variation and shoulder/elbow angles has been investigated for four cases of arm movements (flexion, extension, adduction and abduction). Each arm movement can be characterized by the changes in shoulder angle and the changes in elbow angle at the maximal shoulder angle. In all the four cases of arm movements, the changes of shoulder length and cap height are largest at the maximal shoulder angle. These changes were little affected by changes in elbow angle. The changes in the lower arm length and the difference between cap height and upper arm length are the largest at the maximal elbow angle of the maximal shoulder angle. There is a linear relationship between cap height and shoulder angle during arm movements; thus, in designing sleeves the cap height can be determined from the regression of cap height vs. shoulder angle.

• Journal of Periodontal and Implant Science
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• v.48 no.3
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• pp.174-181
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• 2018

Purpose: The aims of the present study were to quantitatively assess graft height changes after sinus lift procedures and to analyze the factors that influenced graft height changes, including the residual bone height before surgery, surgical approach, and tooth type. Methods: A total of 39 maxillary posterior implants placed during a simultaneous sinus lift procedure were evaluated. Panoramic radiographs of all patients were taken immediately after implant installation and at 3 months, 6 months, 1 year, 2 years, and 3 years. To analyze graft height changes over time, we measured the distance between the implant platform and the base of the grafted sinus floor at 3 locations. The radiographs were analyzed by a single examiner. Results: Graft height tended to decrease over time, and a statistically significant difference was observed at 2 years compared to baseline (P<0.05). There was no statistically significant difference in graft height change according to the surgical approach or tooth type. For residual bone height, a statistically significant difference in graft height change was found between those with 4-7 mm of residual bone height and those with ${\geq}7mm$ (P<0.05). Conclusions: Graft height after sinus lift procedures significantly decreased at 2 years compared to baseline after sinus augmentation. Further studies should be done with controlled variables, and prospective studies with 3-dimensional images are needed to clarify the factors that influence graft height changes.

• The korean journal of orthodontics
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• v.35 no.3 s.110
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• pp.174-181
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• 2005

Understanding the level of a person's perception of changes that have occurred on the face after orthodontic treatment is critical to the process of orthodontic diagnosis and treatment planning. The purpose of this study was to determine the level of perception of profile and frontal changes in lower facial height. Forty students attending art school participated in a study evaluating the level of a participant's perception of changes in the lower facial height. Participants compared computer-graphic frontal and profile photographs with balanced proportions and photograph simulations of 1, 2, 3, and 4mm changes in lower facial height from stomion to the chin. At least a 2 mm change in lower facial height for the profile view and 3mm in the frontal view was needed to be perceived after orthodontic treatment. The level of a person's perception of the change in lower facial height was more sensitive in the profile view than in the frontal view, and information about facial changes given prior to evaluation enhanced the level of perception.

• Atmosphere
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• v.23 no.4
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• pp.367-375
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• 2013

We present here the future changes in vertical distribution of temperature and tropopause height using the HadGEM2-AO climate model forced with Representative Concentration Pathways (RCPs) scenarios. Projected changes during the 21st century are shown as differences from the baseline period (1971~2000) for global vertical distribution of temperature and tropopause height. All RCP scenarios show warming throughout the troposphere and cooling in the stratosphere with amplified warming over the lower troposphere in the Northern Hemisphere high latitudes. Upper troposphere warming reaches a maximum in the tropics at the 300 hPa level associated with lapse-rate feedback. Also, the cooling in the stratosphere and the warming in the troposphere raises the height of the tropopause.

• The korean journal of orthodontics
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• v.8 no.1
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• pp.39-48
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• 1978

The growth changes in craniofacial depth and height from seven to eleven years of age have been studied in thirty two Korean children, consisted of seventeen boys and fifteen girls. The data was obtained from lateral cephalometric radiographs analyzed by the Coben's coordinate system, and the main conclusions might be summarized as follows. 1. Among the craniofacial depth increments the lower facial depth dimension increased the most, mid-facial depth dimension increased loss, and cranial depth dimension increased the least. 2. In spite of the increasing depth dimensions, the mid-facial depth proportion had a tendency to remain stable. 3. The degree of overbite increased markedly from seven to eleven years of age. 4. Increment in the total anterior facial height dimension was larger than that in the total posterior facial height, and the upper anterior facial height increased more than the lower anterior facial height. 5. The lower facial depth proportion increased markedly, and the convexity of the face was reduced significantly. 6. The posterior facial height tended to show small proportional changes. 7. The growth increments in craniofacial complex were larger in the facial height than in the facial depth.

• Korean Journal of Applied Biomechanics
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• v.24 no.1
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• pp.67-74
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• 2014

This study researched into the left-right inclination of the rear foot at the lower limb joints, knee joint angle, angular velocity of the knee joint, angular acceleration and the max. Based on the analysis of kinematics according to the changes in the height of step box (6, 8, 10 inches) during step aerobics of female college students majoring in physical education. The findings of this study are as follows: Then angle of the knee joint decreased as the height of the step box increased the min. Angle was measured right before the right foot was on the step box, and the angle tended to decrease as the step box get heightened. The left-right inclination of the rearfoot angle according to the height of step box increased as the height increased. In the 'pull-up' stage during which the weight was loaded on the right foot the angle increased, while in the right foot stepping stage during which the right foot was on the ground, the left-right inclination of the rearfoot angle increased as the height of the step box increased. The angular velocity of the knee joint according to the height of step box started increasing when the right foot initially stepped on the step box and during the initial stepping section, the angular velocity decreased as the height of step box increased. The changes in angular acceleration of the knee joint according to the height of step box increased as the height of step box increased.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.5 no.2
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• pp.73-84
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• 2007

This study aims to examine changes from differences in the lumbar scoliosis angle and iliac crest height due to abnormal and habitual posture shown in unilateral weight load at standing posture and suggest data for preventing and treating lumbago. The subjects of this study are 16 lumbago patients between twenties and forties with chronic lumbago over six months, but without neurological symptoms. As a result of photographing front and back with three conditions such as weight load on both sides and left or right unilateral weight load posture in order to examine changes of lumbar scoliosis and iliac crest according to changes of posture at unilateral weight load, while scoliosis angle and iliac crest height by habitual unilateral support were increased, those by opposite support were decreased. In conclusion, it was found that habitual unilateral weight load may cause continuous distortion of spinal angle and change of iliac crest height and these may be a factor of lumbago. Therefore, if habitual unilateral weight load state is kept continuously, distortion of lumbar angle and iliac crest height may be greater and common efforts to change habitual unilateral weight load are needed.

• The korean journal of orthodontics
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• v.30 no.5 s.82
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• pp.599-611
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• 2000

Alveolar crest is the section of interproximal alveolar bone which includes the free edge of the alveolar process. An increase of the normal forces within limits of tolerance leads to deposition of new bone. If forces are beyond the limits of tolerance, resorption of bone will result whether the force produces pressure or tension. This study was designed to evaluate changes of alveolar bone levels in mesial and distal surface of the left, right first molar, by using pre-treatment, post-treatment panorama films. Two hundreds sixteen subjects were divided into adolescent group of 104 subjects and adult group of 112 subjects, to which orthodontic treatment with a bicuspid extraction (adolescent group-50 subjects, adult group-50 subjects) or without a nonextraction (adolescent group-54 !subjects, adult group-62 subjects) was applied by fixed appliances. Pre- and post-treatment Panorama films were traced, and alveolar crest height was measured. Amounts of changes in alveolar crest height by treatment were calculated md compared in terms of side of tooth, extraction, age. The results were as follows ; 1. When pre-treatment alveolar crest bone levels were compared, levels of adult group were significantly lower than those of adolescent group. 2. Post-treatment alveolar crest bone levels were significantly lower than pre-treatment levels. 3. When changes of alveolar crest height were compared, between adolescent and adult group were not significantly. 4. When changes of alveolar crest height were compared, significantly larger changes were noticed in ex윤action than nonextraction cases. 5. When changes of alveolar crest height were compared, significantly larger changes were noticed in maxilla than mandible. 6. When mesio-distally compared, significantly larger changes were observed in the distal than mesial sides of adult group.

• The Research Journal of the Costume Culture
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• v.23 no.4
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• pp.604-615
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• 2015

The objectives of this study were to investigate whether heel height changes in the U.S. market occur in a cyclical pattern and heel heights show greater within-year variability over time. Heel height data from U.S. Vogue's spring and fall editions were analyzed over the time period 1950~2014. A total of 1581 pieces of data were measured in millimeter units using Adobe Illustrator and standardized by dividing the height of the heel by the shoe length through the curved sole line. To analyze the cycle pattern of heel heights, the yearly averages were standardized by using three-year moving average technique to average out the irregular components of time series data and give a better indication of the long-term fluctuation of heel height. To identify the degree of within-year variability of heel height, the standard deviation of the average measurements for a year was calculated, and then decade averages were drawn from the yearly averaged standard deviation. One-way ANOVA was conducted to compare the within-year variability of data in heel height over the time period studied by decade. The results showed: First, there was a trend toward higher heels from the early 1950s to 2011. Second, four cyclical movements of heel height were observed from 1950 to 2007, and heel heights gradually decreased after 2008. Third, the within-year variability significantly increased over time, especially after the 1980s.

• Journal of the Ergonomics Society of Korea
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• v.35 no.1
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• pp.39-52
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• 2016

Objective: This paper investigates gait changes according to different heel heights and speeds, and the interaction between the effects of the heel height and the speed during walking on stride parameters and joint angles. Furthermore, the relationship among heel height, speed and gait variables is investigated using linear regression. Background: Gait changes by heel height or speed have been studied respectively, but has not been reported whether there is an interaction effect between heel height and speed. It would be necessary to understand how gait changes when a person wears heels in different heights at various speeds, for example, high-heeled walking at fast speed, since it may cause unusual gait patterns and musculoskeletal disorders. Method: Ten females were asked to walk at five fixed cadences (94, 106, 118, 130 and 142 steps/min.) wearing three shoes with different heel heights (1, 5.4 and 9.8cm). Nineteen gait variables were analyzed for stride parameters and joint angles using two-way repeated measure analysis of variance and regression analysis. Results: Both heel height and speed affect movement of ankle, knee, spine and elbow joint, as well as stride length and Double/Single support time ratio. However, there is no significant interaction effect between heel height and speed. The regression result shows linear relationships of gait variables with heel height and speed. Conclusion: Heel height and speed independently affect stride parameters and joint angles without a significant interaction, so the gait variables are linearly amplified or diminished by the two factors. Application: Walking in high heels at fast speed should be careful for musculoskeletal disorders, since the amplified movement of knee and spine joint can lead to increased moment. Also, the result might give insight for animators or engineers to generate walking motion with high heels at various speeds.