• Korean Journal of Applied Biomechanics
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• v.15 no.1
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• pp.197-206
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• 2005

The purpose of this study was to quantify the maximum EMG levels and determine if there are differences in these EMG levels with respect to different knee flexion angles. Eight university students with no known musculoskeletal disorders were recruited as the participants. The maximum voluntary isometric knee extensions and flexions were taken from each participant sat on the isokinetic exercise machine (Cybex 340) at five different knee flexion angles ($10^{\circ}$, $30^{\circ}$, $50^{\circ}$, $70^{\circ}$, $90^{\circ}$) After surface electrodes were attached to rectus femoris, vastus medialis, vastus laterlis, biceps femoris, and semitendinosus, maximum EMG levels at five different knee flexion angles were measured. The results showed that there was no significant difference in maximum EMG levels among five different knee flexion angles. Although there was no significant difference in EMG levels and were some variations among different knee flexion angles, the EMG signals of quadriceps in extension and biceps femoris in flexion were the greatest at $30^{\circ}$. It seems that different joint angles or relative locations of body segments might affect the magnitude of EMG levels. Because the maximum EMG levels could change with a different knee flexion angle, an attempt should be made to more accurately measure these values. If then, %MVIC measure provides more reliable data and is most appropriate for EMG normalization.

• Archives of Plastic Surgery
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• v.33 no.5
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• pp.592-600
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• 2006

Purpose: Numerous materials, both autologous and nonautologous, have been used for augmentation of sunken areas, but they have their own limitations. The purpose of this study is to determine the histologic response and volume change of the xenogenic collagen-based scaffold($Terudermis^{(R)}$) to the transfer into a subcutaneous soft tissue location in vivo rabbit model. Methods: Eighteen New Zealand white rabbits were used. Three $1.2{\times}1.2cm$ sized subcutaneous pockets were created on the dorsal surface of each ear. $1{\times}1cm$ sized collagen matrix($Terudermis^{(R)}$) and autologous dermal graft were implanted into each pocket. Full thickness of ear was harvested in 3 days, 1, 2, 4 weeks, 3, 6 months after implantation. Results: Histological analysis of implants demonstrated progressive neovascularization, fibroblast infilteration, neocollagen bundle synthesis and organization, and few foreign body reaction. The thickness of the collagen matrix in 3 days after the operation was 87.69% of the thickness of the collagen matrix in wet state. Then it decreased to 30.17% in 6 months after the operation. The rate of decrease was similar at all points at the same time compared with autologous dermal graft. Conclusion: Our experimental study suggests that $Terudermis^{(R)}$ could be a safe material as an implant for permanent augmentation in subcutaneous tissue. However the choice of graft for augmentation should be remained to the clinical situations.

• The Research Journal of the Costume Culture
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• v.6 no.1
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• pp.136-148
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• 1998

This is a study on the change of the Medievalmen's underclothes. Underclothing includes all such articles, worn by either sex, as were completely or mainly concealed from the spectator by the external costume. Throughout the Middle Ages, the underclothing of both sexes possessed characteristic inherited from earlier times. Its function was purely utilitarian. It was not used to express class distinction and only very indirectly to enhance sex attraction. The idea of underclothes was associated with the idea of the body's sinfulness. Underclothes could also symbolize the discipline of humility. To appear clad only in underclothes was a voluntary form of selfabasement often practised by pilgrims. The notion that underclothes might express the spirit of the changing times, in sympathy with the outer clothing, did not enter the medieval mind. The length of the shirt was less than that of the modern garment, especially after the middle of the fourteenth century. The sleeves were somewhat full, without cuffs, and cut straight. During the second half of the twelfth century, when braies become definitely an undergarment. In the fourteenth century braies became shorter and shorter and the shirt could no longer be tucked in but hung outside over the thighs. After 1340 the costume on the surface somewhat resembling modern 'tights', began to reveal display the shape of the male leg as a form of sex attraction. By the close of the Middle Ages, braies had become less like loincloths, and more like modern bathing trunks. The peasant and laborer did not attempt to keep pace with the changes of fashion but, continued, as a rule, to wear the long braies of their forefathers. The higher ranks how this garment reflected the changes of the mode of outer costumes.

• The Research Journal of the Costume Culture
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• v.21 no.4
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• pp.606-611
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• 2013

It has been reported that tight sportswear could have complicated influence on physiological function of human body. The purpose of this present study was to investigate the effect of wearing gradient compression tights (GCT) on muscle strength and EMG activity during repeated isokinetic muscle contractions. Four healthy male undergraduate students performed maximal voluntary isokinetic concentric muscle contractions on biomechanical test and training systems with GCT and loose pants as control (Cont) respectively. During each test, the peak torque of extensor and flexor contractions and the surface electromyography (sEMG) of the rectus femoris and medial gastrocnemius was recorded simultaneously, the peak torque was recorded as an indicator of muscle strength, and the average amplitude and mean power frequency of sEMG were calculated as indicators of EMG activity. The results showed that: the peak torque decreased gradually during continuous muscle contractions both when the Cont and GCT were worn, average sEMG and mean power frequency declined along with the repetitions of muscle contractions for both wearing conditions, and the change tendency was consistence with that of peak torque. There was no obvious difference between the peak torque recorded wearing the Cont or wearing GCT, but when GCT were worn, average sEMG was lower and mean power frequency was higher than the Cont condition. In 24 samples obtained from four subjects, 80% of results showed the same trend. So we could make a conclusion that wearing GCT had no obvious effect on the improvement of muscle strength, but it would affect the EMG activity positivly.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.5
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• pp.754-764
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• 2010

Most silk fabrics are produced only after the degumming process to make the best use of the properties and have restricted silk processing that do not hinder their performance. However, considering the highly increased preference for natural fibers and the shortage of raw silk, high-quality upgraded silk product functions are required by the development of a processing technology and a good design. This study analyzes the changes with the samples by the functional finish such as softening finishing, wash and wear, tannin weighting by measuring the objective hand of scoured silk and three finished ones using KES-FB. As a result, the change of objective hand of finished silk fabrics that improves functionality was analyzed and compared. The increase of KOSHI after the finish became stiffer show that the silk fabric samples are appropriate for summertime clothes with the retention of a certain clothing climate for the body. The stiffness of finished fabrics for the normal had a closer relationship with the density of fabrics than the type of finishing. The samples (after the softening finishes) maintain better elasticity according to the properties of the softener and the finishing agent. Although the specimens of this study were thin fabrics, their elasticity against compression increased after the softening finishes and became softer than degummed silk. The surface properties of georgette were changed by all types of finishing.

• Design & Manufacturing
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• v.12 no.1
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• pp.13-17
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• 2018

It was analyzed and experimented on the change of the material thickness according to the size of the "R" of the punch and die corners using the material of SCP-1 0.25mm As a result, the following conclusions were obtained. Tensile strength analysis and safety analysis of materials are very important process for each process in strip layout, and Through this, the Influx of material and the deformation of the material were found. As a result of safety analysis and tensile thickness analysis, when the corner R of the punch was 0.3 mm and the edge R of the die was 1.0 mm The inflow of the material was not smooth, and the thickness of the corner part became 0.2 mm, causing cracks. when the corner R of the punch was 0.5 mm and the edge R of the die was 1.5 mm The inflow of the material was smooth, The thickness of the corners of the product is 0.21mm and It was considered that cracks do not occur when the thickness of the bottom surface and the body part becomes thin. The results obtained by applying the results obtained from the analysis, In Experimental Condition 1, a crack occurred in the same part of the analysis In Experimental Condition 2, the flow of the material was smooth and the drawing processing could be performed without generating cracks.

• Journal of the Korean Chemical Society
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• v.38 no.7
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• pp.473-479
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• 1994

Tungsten thin film was deposited on p-(100) silicon substrate by using the LPCVD(low pressure chemical vapor deposition) technique. $WF_6$ was used as a source gas for tungsten and $SiH_4$ was used as a reducing gas for $WF_6$. Tungsten thin film was deposited by either SiH4 or Si substrate reduction of $WF_6$ under cold-wall condition and it was deposited by $SiH_4$ reduction of $WF_6$ under hot-wall condition. The crystal structure of deposited thin film under both conditions were identified to be bcc (body centered cubic). The physical and electrical properties of deposited thin films were investigated. The deposited film under hot-wall condition changed to $WSi_2$ film by the annealing under $800^{\circ}C.$ From the experimental results and theoretical considerations, the change of the crystal structure of the thin film by annealing was discussed. $WSi_2$ thin film, which was known to have good compatibility with Si substrate, could be produced under hot-wall condition although the film properties were superior under cold-wall condition.

• Korean Institute of Interior Design Journal
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• v.17 no.3
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• pp.86-93
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• 2008

The purpose of this study is to find out how the otherness philosophy reveals itself in the principle of F.O.A construction space creation. The traditional philosophy of totality is self-centered and thoughts are based on the subject. It couldn't escape from the world associated with the self, and has subordinated the other to the main body. But the philosophy of otherness transcends the subject, to the open, creative way of thinking which acknowledges deconstruction, decentralization, and non-hierarchy. This is very similar to contemporary architecture, which pursuits change, and also to the current state of society. In construction by the construction group F.O.A, which is doing notable activity this generation, there is an attempt to transcend the fixed subject which is seen in the otherness discussion, and realize recategorization by overcoming the boundaries of subject and object. First, by the realization of landscape architecture using a topographical folding technique, boundaries of the subject and object are demolished in the relationship of the landscape construction, and recategorization. Second, by breaking up the meaning of the surface which is a visual and physical boundary for both the internal and external, recategorization is being done. Third, by making the boundary between the interior and exterior indistinct, cognitive threshold is dissolved, and the relationship between the subject and object is being recategorization. In conclusion, we can see that the many recategorization phenomenons that are happening in the F.O.A construction show the otherness that escapes from the conventional and stationary relationship, and recognizes each other at the same time, forming new relationships.

• The Journal of Korean Physical Therapy
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• v.23 no.1
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• pp.1-5
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• 2011

Purpose: The purpose of this study was to investigate changes in muscle activation associated with foot position during a sit-to-stand exercise among normally healthy elderly subjects. Methods: Eight subjects (male=3; female=5; mean age=$70.13{\pm}{\pm}2.53$years) were recruited.The activation of six muscles (neck extensor; lumbar extensor; hamstring; rectus femoris; gastrocnemius; tibialis anterior) was measured by surface EMG (TeleMyo 2400T G2, Noraxon Inc., USA) during a sit-to-stand protocol under three different foot positions (ankle dorsiflexion of 0, 15, or 30 degrees). Results: Muscle activation of the neck extensor and hamstring was decreased according to the change in foot position (p<0.05), but activation of the rectus femoris was increased (p<0.05). Muscle activation of the neck extensor was significantly different between 0 and 15 degrees (p<0.05). Muscle activation of the hamstring was significantly different between 0 and 15 degrees and between 0 and 30 degrees (p<0.05). Muscle activation of the rectus femoris was significantly different between 0 and 30 degrees and between 15 and 30 degrees (p<0.05). However, activation of lumbar extensor, gastrocnemius and tibialis anterior muscles did not significantly differ between foot positions. Conclusion: These findings suggest that muscle activation during a sit-to-stand movement differs depending on foot position. We believe that these differences should be considered when educating the elderly regarding proper body movements.

• The korean journal of orthodontics
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• v.49 no.6
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• pp.393-403
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• 2019

Objective: Sliding mechanics using orthodontic miniscrews is widely used to stabilize the anchorage during extraction space closure. However, previous studies have reported that both posterior segment displacement and anterior segment displacement are possible, depending on the mechanical properties of the archwire. The present study aimed to investigate the effect of archwire stiffness and friction change on the displacement pattern of the maxillary posterior segment during anterior segment retraction with orthodontic miniscrews in sliding mechanics. Methods: A three-dimensional finite element model was constructed. The retraction point was set at the archwire level between the lateral incisor and canine, and the orthodontic miniscrew was located at a height of 8 mm from the archwire between the second premolar and first molar. Archwire stiffness was simulated with rectangular stainless steel wires and a rigid body was used as a control. Various friction levels were set for the surface contact model. Displacement patterns for the posterior and anterior segments were compared between the conditions. Results: Both the anterior and posterior segments exhibited backward rotation, regardless of archwire stiffness or friction. Among the conditions tested in this study, the least undesirable rotation was found with low archwire stiffness and low friction. Conclusions: Posterior segment displacement may be unavoidable but reducing the stiffness and friction of the main archwire may minimize unwanted rotations during extraction space closure.