• Korean Journal of Applied Biomechanics
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• v.17 no.2
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• pp.167-176
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• 2007

The purpose of this study was to offer suitable model for performing Tippelt motion and data for training Tippelt motion through the quantitative kinematical analysis of Tippelt motion in parallel bars. The results of analysing kinematic variations through three-dimensional reflection analysis of three members of the national team as the objects of the study were shown as follows. 1. It seemed that the shoulder-joints which are stretched as much as possible affects the whole Tippelt motion while one is swinging downward. The time of process of the center of mass for the body reaching to the maximum flection point should be quick and body's moving from the vertical phase to the front direction should be controled as much as possible. 2. While one is swinging upward, the stability of flying motion could be made certain by the control of body's rapid moving to the front direction and stretching shoulder-joints and hip-joint to reverse direction. 3. While one is flying upward, the body should be erected quickly and lessening the angle of the hip-joint affects the elevation of flight. When the powerful counter turn motion is performed, the stable motion could be made. As a result of this study, It seems that sudden fall and the maximum stretch of shoulder-joints is important during performing Tippelt motion in parallel bars. Also, it concludes that the maximum bending of hip-joints at the starting point of upward swing, sudden stretch to the reverse direction of shoulder-joints and hip-joints when one is leaving bars, control of body's moving to the front direction, and lessening the angle of hip-joints at the flying phase is important.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.2 s.173
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• pp.329-337
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• 2000

An investigation has been performed to develop an analysis tool based on a nonlinear beam theory, which can be used to predict the long-term behavior of an artificial hip joint. The nonlinear behav ior of the femur arise from the coupled dependence of the bone density and the mechanical properties on each other. The beam theory together with its numerical algorithm is developed to take into account the nonlinear bone remodeling process of the femur that is long enough to be assumed as a beam. A piecewise linear curve for the bone remodeling rate is used in the bone remodeling theory and the surface area density of bone is modeled as the third order polynomial function of bone density. At each section of the beam, a constant curvature is assumed and the longitudinal strains are also assumed to vary linearly across the section. The Newton-Rhapson iteration method is used to solve the nonlinear equations for each cross section of the bone and a backward method is used to march along the time. The density and the remodeling signal ar, calculated along with time for the various time steps, and the developed beam theory has been verified by comparing with the results of finite element analysis of a remodeling bone with an artificial hip joint of titanium prosthesis subjected to uni-axial loads and pure bending moment. It is concluded that the developed beam theory can be used to predict the long-term behavior of the femur and thus to design the artificial hip prosthesis.

• Korean Journal of Applied Biomechanics
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• v.22 no.3
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• pp.357-363
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• 2012

The purpose of this study was to investigate the effects of different saddle heights on lower-limb joint angle and muscle activity. Six elite cyclists(age: $32.2{\pm}5.2years$, height: $171.0{\pm}3.5cm$, weight: $79.7{\pm}5.6kg$, cycle career: $13{\pm}6.2years$) participated in three min. submaximal(90 rpm) pedaling tests with the same load and cadence based on saddle heights where subject's saddle height was determined by his knee flexion angle when the pedal crank was at the 6 o'clock position. Joint angles(hip, knee, ankle joints) and the activity of lower limb muscles(biceps femoris(BF), vastus lateralis(VL), tibialis anterior(TA) and gastrocnemius medial(GM)) were compared by measuring 3D motion and electromyography(EMG) data. Results showed that there were significant differences in minimum hip & knee joint angle and range of motion of hip and knee joint between saddle heights. Onset timing and integrated EMG of only BF among 4 muscles were significantly different between saddle heights. Especially there was a negative relationship between minimum hip joint angle and onset timing of BF in most subject, which means that onset timing of BF became fast as the degree of bending of the hip joint became larger by saddle height. Optimal pedaling will be possible through increased amount of muscle activation due to the appropriate burst onset timing by proper pedaling posture with adjusted saddle height.

• Fashion & Textile Research Journal
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• v.22 no.2
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• pp.222-232
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• 2020

This study analyzes changes in the knees, hips, and hip joint length according to the different angles of bending knees by 45°, 90°, and 135° respectively for knees, hips, and the hip joint that have high fracture rates when falling down. The research subjects were 10 elderly women in their 60s (or older) that obtain data collected through direct measurement. For analysis, the study drew a diagram of elongation and shrinkage based on changes and change rate from a straight posture (0°) and conducted a statistical analysis on differences of body surface length by zone according to movements. The more the knees were bent, the vertical surface length in front of the knees, the horizontal surface length above the knee line, the horizontal body surface length below the knee lines on the back, and the vertical surface lengths between front side lines and the side lines increased; however, the vertical surface length on the back decreased. For the hip joint, the difference in the vertical surface length was more distinctive when compared to the horizontal. Finally, the horizontal surface length increased below the hips and the vertical surface length increased in most areas except the sidelines and the front. The result of the change in body surface length according to the movements of this study can be utilized in the development of the motion-variable protector.

• The Journal of Korean Physical Therapy
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• v.11 no.2
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• pp.93-102
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• 1999

Alignment of the hip joint and pelvis affects it's weight-bearing capabilities as well as the motion available at the joints. The normal hip joint is well designed to withstand the forces that act through and around it, assisted by the trabecular systems, cartilagious, muscles, and ligaments. Alterations in the direction or magnitude of forces action around the injury and degenerative changes. The integration of motion of the pelvis with motion of the vertebral column not only increases the ROM available to the total column but also reduces the amount of flexibility required of the lumbar lesion. In any instance in which there is normal or abnormal pelvic motion during weight hearing and the head must remain upright, compensatory motions of the lumber spine will occur if available. The motions that occur at the hip, pelvis, and lumbar spine during forward trunk bending with the motions that occur during anterior and posterior tilting of the pelvis in the erect standing postion.

• Journal of the Korean Home Economics Association
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• v.49 no.3
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• pp.113-121
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• 2011

This study developed a method of calculating dynamic wearing ease (DWE) to make patterns for coverall work clothing. The DWE was measured from 3D body scan data of women in their 20's (n = 10). The body postures adopted for measuring the DWE were sitting and deep bending postures. Three types of experimental patterns (A, B, C) were developed. The DWE was applied at the waist and hip lines of the pattern. The location and size of the DWE varied from one pattern to another. For pattern B, DWE of 8.8cm was applied at the back of the waistline. For pattern C, 5.3cm was applied at the waist for the center back line, and 3.5cm was applied at the under hip level. The comfort of the experimental clothing was evaluated in six body postures. The results showed that patterns B and C were comfortable at the crotch, shoulders, and arm pits. Pattern C was comfortable at the hip and crotch areas in the arms lifting-up posture and the stepping-up posture. The appearance and fit of the experimental clothing were evaluated by the panels. Patterns B and C fitted better than pattern A at the abdomen. The results suggest that DWE should be applied at the waist and hip levels for making coverall work clothing patterns.

• Fashion & Textile Research Journal
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• v.14 no.3
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• pp.454-464
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• 2012

In this study, fitness tests for slacks were divided into shape fitness test and motion fitness test, and the fitness test conditions for slacks were designed as the first step for standardization of measuring scales. Shape fitness test consisted of analyzing the parameters of appearance sensory tests as described in preceding studies, performing a simulated appearance sensory test, collecting and considering apparel experts' opinions about the test parameters, and establishing test conditions in terms of test regions, descriptions and faces. For the regions of the abdomen, hip, crotch, thighs, and knees, the parameter of unnecessary wrinkle/stretch was observed from the anterior and posterior body, and then evaluated; for waist, hip, crotch, knee and hem circumference, the parameters of ease and horizontality were observed from the anterior body and posterior body followed by evaluation; and, at the levels of waist, hip, crotch, knee and hem circumference, the division of the lateral line were observed from the lateral body followed by evaluation. Motion fitness test was composed of reviewing and analyzing comparatively the methods of motion fitness tests as mentioned in preceding studies, and establishing test conditions in terms of test motions and test regions. For each of the waist, abdomen, hip, crotch, and knees, wear sensation was tested in the positions as follows: upright standing, moderate walking, chairsitting, bending forward to the maximum, and kneeling down, provided that as the measured points of garment pressure, anterior waist, abdominal protrusion, buttock protrusion, crotch, and midpatella were set and tested.

• The Journal of Natural Sciences
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• v.8 no.1
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• pp.53-59
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• 1995

Effects of sintering additives and sintering temperatures on the sintering behavior and mechanical properties of SiC whisker reinforced alumina composites have been investigated in this study. Dense (>95% TD) composites were obtained by using 2 wt% $Y_2O_3$ as liquid phase sintering additive. But only porous composite could be obtained when the sintering additives were MgO and $TiO_2$, which were known as the sintering additives for solid state sintering of alumina. Bending strength and fracture toughness were enhanced by reinforcement of SiC whisker. It is belived from the microstructure investigation that the enhanced by strength and toughness could be attribute to the reinforcing and grain growth inhibition effects of SiC whisker. After HIP treatment, fully dense composites were obtained and further enhanced mechanical properties achieved.

• The Korean Journal of Rehabilitation Nursing
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• v.6 no.2
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• pp.239-247
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• 2003

Purpose: The purpose of this study is to examine how well patients who had hip arthroplasty comply with medical regimens given to them after the operation. Method: The subjects of the study were patients who had arthroplasty at P Hospital between April 1, 2001 and August 30, 2002. 20 patients of the subjects experienced complications after the operation and the other 20 did not. Data from a survey using the qustionnaire were statistically analyzed in terms of real number, percentage point, mean and standard deviation by using $X^2$-test, t-test and ANOVA. Result: 1) the surveyed patients were significantly different in the compliance of medical regimen among them according to their education background as one of the subjects general characteristics. 2) It was found that the group of complication was higher in the compliance of medical regimen than that of non-complication. The two groups showed statistically significant difference with each other in the degree of compliance with therapeutic instructions than the experimental group in terms of the maintenance of abduction after the operation, training instructions on step-by-step basis, urination cotrol on bed, accurate use of crutch, compliance with medication, balance among medical treatment, training, leisure, rest and nutrition, instructions by physicians, nurses and physical therapists, use of low armchairs and toilet bowels and no bending of the body forward, and use of a non-operated leg in case of go upstairs or downstairs. Conclusion: It seems necessary to develop systematic and sessional education programs for improving the compliance of medical regimen, ultimately reducing complications following hip arthroplasty.

• Journal of the Korean Home Economics Association
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• v.34 no.2
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• pp.183-199
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• 1996

The objective of this study was to provide fundamental data on somatotype for elderly women by classifying the somatotype and analysing the 3 characteristics of their somatotype. The subject were 368 women of 60~84 years old, they were analyzed indirect photography. To find out differences among the age groups, the 368 subjects were grouped into two age groups (Group 1 ; age 60 to 69, Group 2 ; aged 70 to 84). Data were analyzed using Factor analysis, Cluster analysis, duncan test and Analysis of variance. Through the factor analysis, 27 items from photometric measurements respectively. Cluster analysis was applied for classification of somatotype. The results of this study were as follows. 1. The characteristics of Elderly women's somatotype were bending of the upper-torso, fatness of the waist and abdomen, drooping of the bust and shoulder and hip. In addition, height, girth, depth and width items were decreased in their sizes respectively. 2. The characteristics of clusters were as follows. Type 1 was straight somatotype in which the plumb line through tragion, the bust depth and under bust depth region laterally. Type 2 was swayback somatotype in which the upper portion of protruding point on the back was bent forward but the lower portion of protruding point had a characteristics of turning over somatotype. Type 3 was bending somatotype. Namely, this type was shorter than average and below the average fatness. Generally, the lateral view silhouette of elderly women was the straight type and changed into bending type as the age increases.