• Title/Summary/Keyword: functional plastic

Search Result 659, Processing Time 0.032 seconds

A Comparative Study for Incompressibility of Rigid Plastic Finite Element Method (강소성 유한요소법에서 비압축성조건에 관한 비교 연구)

  • 이상재;조종래;배원병;김영호
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • 1997.10a
    • /
    • pp.57-61
    • /
    • 1997
  • The governing functional in plastic deformation has to satisfy the incompressible condition. This incompressible condition imposed on the velocity fields can be removed by introducing either the Langrange multiplier or the penalty function into the functional. In this study two-dimensional rigid plastic FEM programs using by Langrange multiplier and penalty function are developed. A compression of cylinder and a spike forging are simulated to compare the data of loads, local mean stresses and reductions of volume.

  • PDF

Comparative Study of Spiral Oblique Retinacular Ligament Reconstruction Techniques Using Either a Lateral Band or a Tendon Graft

  • Oh, Jae Yun;Kim, Jin Soo;Lee, Dong Chul;Yang, Jae Won;Ki, Sae Hwi;Jeon, Byung Joon;Roh, Si Young
    • Archives of Plastic Surgery
    • /
    • v.40 no.6
    • /
    • pp.773-778
    • /
    • 2013
  • Background In the management of mallet deformities, oblique retinacular ligament (ORL) reconstruction provides a mechanism for automatic distal interphalangeal (DIP) joint extension upon active proximal interphalangeal joint extension. The two variants of ORL reconstruction utilize either the lateral band or a free tendon graft. This study aims to compare these two surgical techniques and to assess any differences in functional outcome. As a secondary measure, the Mitek bone anchor and pull-in suture methods are compared. Methods A single-institutional retrospective review of ORL reconstruction was performed. The standard patient demographics, injury mechanism, type of ORL reconstruction, and pre/postoperative degree of extension lag were collected for the 27 cases identified. The cases were divided into lateral band (group A, n=15) and free tendon graft groups (group B, n=12). Group B was subdivided into the pull-in suture technique (B-I) and the Mitek bone anchor method (B-II). Results Overall, ORL reconstructions had improved the mean DIP extension lag by $10^{\circ}$ (P=0.027). Neither the reconstructive technique choice nor bone fixation method identified any statistically meaningful difference in functional outcome (P=0.51 and P=0.83, respectively). Soft-tissue injury was associated with $30.8^{\circ}$ of improvement in the extension lag. The most common complications were tendon adhesion and rupture. Conclusions The choice of the ORL reconstructive technique or the bone anchor method did not influence the primary functional outcome of extension lag in this study. Both lateral band and free tendon graft ORL reconstructions are valid treatment methods in the management of chronic mallet deformity.

The Development of Functional $TiO_2$-Biodegradable Plastic Composite Material by Thermal Spraying (용사를 이용한 고기능 $TiO_2$-생분해성 플라스틱 복합재료의 개발)

  • ;;Akira Ohmori;Takahiro Nakatsuji
    • Proceedings of the KWS Conference
    • /
    • 2004.05a
    • /
    • pp.316-318
    • /
    • 2004
  • In recent years, plastic waste has been recognized as a worldwide environmental issue. To solve the disposal problem of the plastic waste, alternative treatment such as the use of biodegradable plastic(polybutylene succinate: PBS) is indeed highly in demand due to its merit of PBS buried in soil decomposed into carbon dioxide and water. In the present study, for the production of further functional PBS with TiO$_2$ as photocatalyst, which shows the decomposition of detrimental organic compound and pollutant under ultraviolet irradiation, we attempted to prepare photocatalytic TiO$_2$ coatings on PBS substrate by HVOF and plasma spraying techniques under various conditions using three kinds of agglomerated powders (P200: 200nm, P30: 30nm, P7: 7nm). The microstructures of coatings were characterized with SEM and XRD analysis, and the photocatalytic efficiency of coatings was evaluated through the photo degradation of gaseous acetaldehyde. Therefore, such functional TiO$_2$-Plastic composite material is expected to considerably contribute to the reduction of aggravated environmental problem.

  • PDF

Thermal Degradation Behavior and Reliability Analysis of Plastic Materials for Household Electric Appliances (가전제품용 플라스틱 재료의 열분해 거동 및 신뢰성 평가)

  • Im, Chang-Gyu;Kim, Jun-Young;Kim, Seong-Hun
    • Polymer(Korea)
    • /
    • v.29 no.5
    • /
    • pp.508-517
    • /
    • 2005
  • The thermal degradation behavior and reliability analysis were investigated using dynamic thermogravimetric analysis (TGA) and accelerated degradation test (ADT) to characterize the dynamic parameters related to thermal degradation of plastic meterials for household electric appliances. In addition, the weathering of the plastic were performed by ADT using Xenon uc, and the color difference of the samples after ADT were measured with Color Eye 3010 specoophotometer. he activation energy for thermal degradation of the samples increased with increasing the rate of weight loss. The Kim-Park method was found to be more effective analysis in describing thermal degradation of plastic meterials. Plastic materials were very sensitive to ultra-violet rays in faster degradation.

The Comparison between Anterolateral Thigh Free Flap and Radial Forearm Free Flap in Partial Glossectomy Defect - An Evaluation of Donor Site Morbidity and Functional Outcome (유리 전외측 대퇴부 피판과 유리 요측 전박피판을 이용한 설재건 시공여부 및 기능적 결과 비교)

  • Cho, Sang Hyun;Lee, Won Jai;Lew, Dae Hyun;Tark, Kwan Chul
    • Archives of Plastic Surgery
    • /
    • v.34 no.3
    • /
    • pp.330-335
    • /
    • 2007
  • Purpose: The purpose of this study is to evaluate the functional outcome and donor site morbidity of anterolateral thigh free flap(ALT) compared to Radial forearm free flap(RFFF) for the reconstruction of partial glossectomy defect. Methods: 5 ALT free flap (group I) were attempted for partial glossectomy patients. We compared patients undergone ALT flap with those(n=11) of similar size defect reconstructed with RFFF (Group II). Rating scales for articulation and swallowing function were applied and donor site morbidity have been evaluated. Results: The scales for speech function showed no difference between the two groups (average score; group I - 6.4, group II - 6.45). Swallowing function also showed no difference between the two groups(average score; Group I - 6.6, Group II - 6.27). ALT group had one patient with donor site morbidity(numbness). All of the RFFF patients(11/11) complained and suffered from hypertrophic scar, retraction, numbness or hyperpigmentation on forearm donor site. Based on our study, ALT free flap is comparable to that of RFFF in terms of functional assessment in tongue reconstruction. Conclusion: Considering the donor site morbidity, ALT flap is to be valuable to reconstruct partial glossectomy defect.

Management of the Sequelae of Severe Congenital Abdominal Wall Defects

  • Fuentes, Sara;Marti, Eunate;Delgado, Maria-Dolores;Gomez, Andres
    • Archives of Plastic Surgery
    • /
    • v.43 no.3
    • /
    • pp.258-264
    • /
    • 2016
  • Background The survival rate of newborns with severe congenital abdominal wall defects has increased. After successfully addressing life-threatening complications, it is necessary to focus on the cosmetic and functional outcomes of the abdominal wall. Methods We performed a chart review of five cases treated in our institution. Results Five patients, ranging from seven to 18 years of age, underwent the following surgical approaches: simple approximation of the rectus abdominis fascia, the rectus abdominis sheath turnover flap, the placement of submuscular tissue expanders, mesh repair, or a combination of these techniques depending on the characteristics of each individual case. Conclusions Patients with severe congenital abdominal wall defects require individualized surgical treatment to address both the aesthetic and functional issues related to the sequelae of their defects.

Free Flap Reconstruction in Patients with Traumatic Injury of the Forefoot

  • Kang, Shin Hyuk;Oh, Jeongseok;Eun, Seok Chan
    • Journal of Trauma and Injury
    • /
    • v.32 no.3
    • /
    • pp.187-193
    • /
    • 2019
  • Many techniques have been developed for reconstruction of the hand; however, less attention has been paid to foot reconstruction techniques. In particular, reconstruction of the forefoot and big toe has been considered a minor procedure despite the importance of these body parts for standing and walking. Most of the weight load on the foot is concentrated on the forefoot and big toe, whereas the other toes have a minor role in weight bearing. Moreover, the forefoot and big toe are important for maintaining balance and supporting the body when changing directions. Recently, attention has been focused on the aesthetic appearance and functional aspects of the body, which are important considerations in the field of reconstructive surgery. In patients for whom flap reconstruction in the forefoot and big toe is planned, clinicians should pay close attention to flap survival as well as functional and cosmetic outcomes of surgery. In particular, it is important to assess the ability of the flap to withstand functional weight bearing and maintain sufficient durability under shearing force. Recovery of protective sensation in the forefoot area can reduce the risk of flap loss and promote rapid rehabilitation and functional recovery. Here, we report our experience with two cases of successful reconstruction of the forefoot and big toe with a sensate anterolateral thigh flap, with a review of the relevant literature.

A Study on the factors for determining the layout of plan in Plastic Surgical Clinic - Focused on the after 2000's in domestic cases - (성형외과 의원의 평면 결정 요인에 관한 연구 - 2000년 이후 국내 사례를 중심으로 -)

  • Park, Bo-Hye;Moon, Jung-Mook
    • Korean Institute of Interior Design Journal
    • /
    • v.17 no.6
    • /
    • pp.161-169
    • /
    • 2008
  • Recently, appearance is recognized as competitiveness as well as self expressing means, so understanding of general people have been rapidly changed. Also, since modem people have interest in an operation as well as various cosmetic treatment fields, a plastic surgery clinic is expanding its region to laser treatment and skin care for modem people. However, the plastic surgery clinic is not located in a building for only hospitals, but located in general neighborhood living facilities or an office building, so medical treatment is performed at the place. It is often found that a building plan can not conform to conditions that the hospital requires. This study is to understand a plane deciding factor of the plastic surgery clinic by analyzing it in a limit of building space and functional aspects of the plastic surgery clinic. A study method is first to investigate space composition according to the function, area allocation according to the function and a space privacy region after classifying study objects into large, middle, small scales so as to understand a functional role of the plastic surgery clinic, and secondly to analyze on the base of length of long and short edges of space and a moving line system after classifying common space types of the plastic surgery clinic through plane analysis of the study objects. As a result of the study, functional space difference according to the scale was shown, and the common space types were affected by length of the long and short edges, and it can influence space composition.

Reducing the donor site morbidity in radial forearm free flaps by utilizing a narrow radial forearm free flap

  • Shaikh, Safdar Ali;Bawa, Amber;Shahzad, Noman;Yousufzai, Zara;Ghani, Muhammad Shahab
    • Archives of Plastic Surgery
    • /
    • v.45 no.4
    • /
    • pp.345-350
    • /
    • 2018
  • Background The radial forearm free flap (RFFF) has remained a leading choice of many plastic surgeons as a fasciocutaneous flap due to its versatility, pedicle length, and simple elevation technique. However, donor site morbidity has led many reconstructive surgeons to limit their use of the RFFF and to use other flaps instead. We propose that using a narrow RFFF (nRFFF) decreases the aesthetic and functional morbidity of the donor site. Methods We report our experiences with the nRFFF from April 2012 through May 2015 at the Department of Plastic, Reconstructive, and Hand Surgery at Liaquat National Hospital, Karachi. The donor defects were closed primarily. The Stony Brook Scar Evaluation Scale and comparison with the contralateral hand were used to assess aesthetic and functional outcomes, respectively. Results A total of 24 patients underwent nRFFF procedures during the study period. The donor arm showed excellent motor function in 22 cases (91.7%), and very good function in the remaining two cases (8.3%). The aesthetic outcomes were excellent in four patients (16.6%), very good in eight patients (33.3%), good in 10 patients (41.6%), and fair in two patients (8.3%) who developed a hypertrophic scar. All flaps were successful and there were no cases of partial or complete loss. Conclusions For small to medium-sized soft tissue defects, the nRFFF had acceptable outcomes due to its thinness, pliability, and major reduction in donor site aesthetic and functional morbidity.