• The Journal of Korea Robotics Society
• /
• v.19 no.1
• /
• pp.39-44
• /
• 2024

This study introduces a novel method for predicting the shape of soft catheter robots embedded with electromagnets. As an advancement in the realm of soft robotics, these catheter robots are crafted from flexible and pliable materials, ensuring enhanced safety and adaptability during interactions with human tissues. Given the pivotal role of catheters in minimally invasive surgeries (MIS), our design stands out by facilitating active control over the orientation and intensity of the inbuilt electromagnets. This ensures precise targeting and manipulation of the catheter segments. The research encompasses a comprehensive breakdown of the magnetic modeling, tracking algorithms, experimental layout, and analytical techniques. Both simulation and experimental results validate the efficacy of our method, underscoring its potential to augment accuracy in MIS and revolutionize healthcare-oriented soft robotics.

• Archives of Reconstructive Microsurgery
• /
• v.23 no.2
• /
• pp.65-69
• /
• 2014

Purpose: Soft tissue reconstruction is essential for recovery of finger function and aesthetics in any traumatic defect. The authors applied a reverse homodigital artery island flap for soft tissue defect on distal part of digits. The aim of this study is to evaluate the efficacy of the procedure. Materials and Methods: Seven cases of soft tissue defects of finger tip were included in this study. There were six male and one female, mean age was 43 years and mean follow-up period was 38 months. The length of flaps ranged from 2.0 to 2.5 cm and width ranged from 1.0 to 2.0 cm. Flap survival, postoperative complications were evaluated. Results: All flaps survived without loss. Donor sites were repaired with primary closure in five cases and skin graft in two cases. None of the patients showed significant complications and their average finger motion was $255^{\circ}$ in total active motion at the last follow-up. Conclusion: The authors suggest that the reverse homodigital artery island flap could be a versatile treatment option for the soft tissue defect on distal part of digits.

• The Journal of Korean Academy of Prosthodontics
• /
• v.25 no.1
• /
• pp.137-154
• /
• 1987

The purpose of this investigation was to determine the surface characteristics and the fittness of the resilienct denture lines. Firstly, 50 samples ($2.0{\times}4.0{\times}0.3cm$) of 4 resilient lining materials (Molloplast B, Coe Super Soft, Mollosil, Coe Soft) and one conventional acrylic resin (K-33) were processed according to manufacture's direction and examined the surface characteristics by use of surface profilometer and scanning electron microscopy. Secondly, 50 identical maxillary casts were made and 50 denture bases were pro cessed of 4 resilient liners and one conventional acrylic resin and they were stored in the room temperature water bath of 1 day, 1 week, 2 weeks, 3 weeks, 4 weeks and 6 weeks after processing. The original casts were cut away 1 cm from the posterior border, the dentures were seated, and the existing space was measured at seven regions according to the storage time by use of the modified thickness guage. The results were as follows. 1. Surface roughness (Rz) were $4.00{\pm}1.60{\mu}m$ in Mollosil, $4.47{\pm}2.21{\mu}m$ in Molloplast B, $7.46{\pm}1.70{\mu}m$ in Coe Super Soft, $12.70{\pm}2.39{\mu}m$ in Coe Soft and $13.03{\pm}2.74{\mu}m$ in K-33. 2. The generation of porosity was far more active in cold-cured resilient liners (Coe Soft and Mollosil) than in heat cured resilient liners (Molloplast B, and Coe Super Soft) and conventional heat cured resin (K-33). 3. Denture bases showed the greatest discrepancy at the central portion of the posterior palatal border and the intimate contact in the buccal flange regardless of denture base materials. 4. When the denture bases were stored in the water for 1 day and 6 weeks after processing, the sum of average discrepancies in the seven regions of the denture base was the greatest in K-33 followed by Molloplast B, Mollosil, Coe Soft and Coe Super Soft but followed by Coe Soft, Molloplast B, Mollosil, Coe Super Soft in that order respectively. 5. There was not a significant difference (p>0.05) in Coe Super Soft, K-33 but there was a significant difference (P<0.01) in Molloplast B, Mollosil, Coe Soft at the amount of dimensional changes according to the storage time.

• Journal of Fashion Business
• /
• v.11 no.3
• /
• pp.1-14
• /
• 2007

This research to reveal the foot types of old males consisted of two parts. First, a questionnaire was given for 180 old men in their 60s and above who live in Busan. Second, based on this survey on the reality of shoes wearing, direct and indirect measurement were held for 200 old gentlemen. The findings are as follows: 1. Survey Results of Shoes Wearing Reality In the investigation into the reality of shoes possession and wearing, most of old males favored active casual shoes with comfortable materials (40.8%). Hardened skin (23.6%) was the greatest in foot deformation and side effects resulting from shoes wearing, while the big toe (20.1%) was most uncomfortable. The greatest requirement for comfortable shoes was shoes making feet comfortable with a good sense of wear (41.0%), followed by shoes with the soft sole to absorb shock (31.7%), shoes with diverse sizes according to shoes width (13.7%), and shoes made of soft materials in consideration of various foot shapes. 2. Results of Foot Measurement Experiments Busan's males in their 60s and above were 166.31cm (Height), 63.51kg (weight), 23.94cm (foot length), 9.75cm (foot width), and 24.26cm (instep girth). The big toe angle of old males was $11.22^{\circ}$ and the little toe angle $14.70^{\circ}$. Four foot types were classified: 1 (long big foot), 2 (small inside-developed foot), 3 (toe-tip-gathered foot), and 4 (thin flat foot).

• Composites Research
• /
• v.37 no.4
• /
• pp.310-315
• /
• 2024

An auxetic structure with negative Poisson's ratio exhibits distinctive mechanical properties in contrast to conventional structures, garnering interest in various fields. However, current research has predominantly focused on the design and optimization of auxetic structures, with limited exploration of their practical applications. In this study, we utilized 3D printing technology to fabricate a soft auxetic structure with triangular shaped perforations, examining the mechanical properties based on geometric structure. Additionally, by inserting shape memory alloys into the fabricated soft auxetic structure, we achieved active two-dimensional deformations and confirmed its selective object permeability. This technology holds the potential to have far-reaching implications across a broad spectrum of industries.

• Fashion & Textile Research Journal
• /
• v.23 no.4
• /
• pp.423-438
• /
• 2021

This study compared and analyzed the direction of Louis Vuitton creative directors Kim Jones and Virgil Abloh. Accordingly, 485 photos(251 Kim Jones, 234 Virgil Abloh) were collected. For data analysis, statistical and content analyses were combined. First, as for the overall design characteristics of creative director Kim Jones, complex colors, colorful barrels, tone-in-tone color schemes, H-line, plain fabrics, soft materials, heterogeneous material combinations, casual style. Second, as for the overall design characteristics of creative director Virgil Abloh, achromatic color, colorful tone, tone-on-tone color scheme, I-line, plain fabric, soft material, similar material combination, casual style. There were significant differences in color, tone, color scheme, silhouette, pattern, material type, material combination, fashion image, detail, trimming, top and bottom that differed in the creative directors' design direction. Therefore, it appears that Kim Jones has been directing the luxurious and unique men's wear through H-line, coat and slim pants, colorful color combination, soft material, heterogeneous material combination, plain fabric, and chic active sensibility. Meanwhile, Virgil Abloh is directing men's wear in a loose and trendy street mood through the I-line, jacket and wide pants, achromatic color, soft material, plain fabric, similar material combinations, and soft and sophisticated modern sensibility.

• Composites Research
• /
• v.37 no.4
• /
• pp.247-264
• /
• 2024

Recent advances in electro-active polymer (EAP) actuators, owing to their flexibility, lightweight, and simple fabrication process, have showcased their high utility across various fields such as soft robotics, biomimetics, wearable devices, and haptic technologies. Moreover, EAP actuators are evolving into smart devices with new functions and characteristics through the integration of functional materials and innovative technologies. This paper categorizes EAPs into ionic EAPs and electronic EAPs. Ionic EAPs include, most notably, ionic polymer-metal composites (IPMCs) and conducting polymers (CPs), while electronic EAPs encompass dielectric elastomer actuators (DEAs), ferroelectric polymer actuators, and the recently introduced hydraulically amplified self-healing electrostatic (HASEL) actuators. Detailed explanations based on the latest research are provided concerning the mechanism, structure, performance improvement strategies, methods for adding functionality, and application areas for each type of actuator.

• Applied Microscopy
• /
• v.45 no.2
• /
• pp.52-57
• /
• 2015

Bulk metallic glass (BMG) shows higth strength, high elastic limit, corrosion resistance and good wear resistance and soft magnetic properties and has been considering as a candidate for new structural materials. But they show limited macroscopic plasticity and lack of tensile ductility due to highly localized shear deformation, which should be solved for real structural application. In this paper researches on the enhancement of plasticity of BMG were reviewed briefly. Introducing heterogeneous structure in glass is effective to induce more shear transformation zones (STZs) active for multiple shear band initiation and also to block the propagating shear band. Several methods such as BMG alloy design for high Poisson's ratio, addition of alloying element having positive heat of mixing, pre-straining BMG and variety of BMG composites have been developed for homogenous distribution of locally weak region, where local strain can be initiated. Therefore enhancement of plasticity of BMG is normally accompanied with some penalty of strength loss.

• Archives of Reconstructive Microsurgery
• /
• v.19 no.1
• /
• pp.21-28
• /
• 2010

Purpose: To report the clinical results of the use of arterialized venous free flaps in reconstruction in soft tissue defects of the finger and to extend indications for the use of such flaps based on the clinical experiences of the authors. Materials and Methods: Eighteen patients who underwent arterialized venous free flaps for finger reconstruction, between May 2007 and July 2009 were reviewed retrospectively. The mean flap size was 4.7${\times}3.2$ cm. The donor site was the ipsilateral volar aspect of the distal forearm in all cases. There were 8 cases of venous skin flaps, 5 cases of neurocutaneous flaps, 4 cases of tendocutaneous flaps, 1 case of innervated tendocutaneous flap. The vascuality of recipient beds was good except in 4 cases (partial devascuality in 2, more than 50% avascuality (bone cement) in 2). Results: All flaps were survived. The mean number of included veins was 2.27 per flap. Mean static two-point discrimination was 10.5 mm in neurocutaneous flaps. In 3 of 5 cases where tendocutaneous flaps were used, active ROM at the PIP joint was 60 degrees, 30 degrees at the DIP joint and 40 degrees at the IP joint of thumb. There were no specific complications except partial necrosis in 3 cases. Conclusions: An arterialized venous free flap is a useful procedure for single-stage reconstruction in soft tissue or combined defect of the finger; we consider that this technique could be applied to fingers despite avascular recipient beds if the periphery of recipient bed vascularity is good.

• Archives of Reconstructive Microsurgery
• /
• v.17 no.2
• /
• pp.82-86
• /
• 2008

Purpose: Soft tissue defect can occur on the posterior aspect of the elbow after trauma or fracture fixation. To cover the defect and maintain elbow functions, various flap surgeries including latissimus dorsi muscle flap, lateral arm flap and radial forearm flap can be performed. We present the clinical results of transposition lateral arm flap for coverage of the elbow defect and discuss the cause of posterior soft tissue necrosis after fracture fixation. Materials and Methods: Two patients who had posterior soft tissue defect of the elbow after open reduction of the fractures around the elbow were treated with transposition lateral arm flap. The mean size of skin defect was 20 $cm^2$. The flap was elevated with posterior radial collateral artery pedicle and transposed to the defect area. Donor defect was covered with split thickness skin graft. The elbow was immobilized for 1 week in extended position and active range of motion was permitted. Results: All two cases of transposition lateral arm flap survived without marginal necrosis. The average range of motion of the elbow was 10~115 degrees. Mayo elbow performance score was 72 and Korean DASH score was 23. Conclusion: When elbow fractures are fixed with three simultaneous plates and screws, skin necrosis can occur on the posterior aspect of the elbow around olecranon area. If the size of skin defect is relatively small, transposition lateral arm flap is very useful option for orthopaedic surgeons without microsurgical technique.