• Title/Summary/Keyword: Resurfacing

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Design-Build Change Order Impacts in Highway Projects

  • Ryu, Kyeong Rok;Choi, Kunhee;Ryoo, Boong Yeol;Kang, Julian H.
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.371-375
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    • 2015
  • Design-Build (DB) has gained in popularity in roadway projects due to its defining advantage to improve communication and fast-track project delivery. However, very little is known about the impact of change order frequency and occurrence timing pertaining to DB projects. The study analyzes their impacts on project time and cost performance by conducting a rigorous numerical analysis drawing on 530 3R (rehabilitation, reconstruction, and resurfacing) projects completed between 2002 and 2011 in Florida by using a multiple linear regression. The results indicate that DB outperformed Design-Bid-Build in project cost as well as time. Critically, the regression analysis signifies that earlier change order occurrence caused more unfavorable impacts on schedule and cost. The proposed analyses and models will lead to the improved ability of agencies to quickly and more reliably estimate the potential change order impacts on schedule and cost.

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Lower Extremity Reconstruction of Soft Tissue Defects with Perforator Island Flap (하지의 연부조직 결손에 있어 천공지 도서형 피판술을 이용한 재건)

  • Lee, Tae Hoon;Choi, Jae Won;Lee, Jun Ho;Kim, Hyo Heon
    • Archives of Plastic Surgery
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    • v.32 no.4
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    • pp.435-440
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    • 2005
  • The reconstruction of deep soft tissue defects of lower extremities combined with bone exposure has been difficult problems. When it is impossible to raise local skin flap, we have been usually used the gastrocnemius musculocutaneous flap, cross leg flap or free flaps. However, In musculocutaneous flap, aesthetical appearance of the calf is not appropriate because of too bulky flap. Although the success rate of the free flap has improved, still failure of flap occurs in cases of the chronic ischemic state. As the concepts of perforator flap has recently developed and widely used due to its thin flap thickness. Between January 2002 to December 2004, we treated 7 patients with soft tissue defect in leg with chronic ischemic limbs with perforator island flap. Preoperative angiography were done in all case and we used 2 medial sural perforator flaps, 1 anterior tibial artery perforator flap, 1 posterior tibial artery perforator flap, 3 anterolateral thigh perforator flap. Partial necrosis of flap was seen in one patient but no further surgical procedure was required for wound healed spontaneously. Perforator island flaps are thin, reduce donor site morbidity, conceal donor site with primary closure and it is useful for resurfacing soft tissue defect of lower extremities.

The Study of Activation on Nature Interpretation for Odae Mountain National Park (오대산 국립공원의 자연해설 활성화에 대한 연구)

  • Jo Tae-Dong;Joo So-Hyun;Jo Hyun-Ju
    • Journal of Environmental Science International
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    • v.14 no.5
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    • pp.451-455
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    • 2005
  • Surveys for visitor's awareness and on-the-spot investigations at Odae Mountain National Park were conducted for activation of nature interpretation. As a result, many problems on observation trails as the object of the nature interpretation were identified. The nature interpretation is not functioning fully for the side of environmental education. The situation and problems of nature interpretation were analyzed in depth based on the survey of the visitors. In order to improve roles of the nature observation trails and solve the present problems immediately, suggestions are as the followings. I) Road resurfacing and space development needed to solve the problems of existing nature observation trail. 2) Public relations for nature observation trail and production of signboards promoting visitor's interest. 3) Development of nature observation trail used only for nature interpretation 4) Development of adequate Korean interpretation program based on systematic nature interpretation models from other developed countries

A Treatment of Basal cell Carcinoma on the Face of a Xeroderma Pigmentosum Patient: A Case Report (색소피부건조증 환자에서 발생한 안면부 기저세포암의 치료 증례 보고)

  • Bae, Jaehyun;Jun, Dongkeun;Kim, Jeenam;Lee, Myungchul;Shin, Donghyeok;Lim, So Dug;Choi, Hyungon
    • Korean Journal of Head & Neck Oncology
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    • v.36 no.1
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    • pp.39-44
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    • 2020
  • Xeroderma pigmentosum is a rare autosomal recessive disease, related to defects in DNA repair mechanism. It presents skin lesions on sun-exposed areas, leading to various skin cancer. Skin lesions can be treated with cryotherapy, skin resurfacing, 5-FU, Imiquimod, topical T4 endonuclease V, radiotherapy and genetic therapy, but invasive skin cancer should be treated by a surgery. We report a 12-year-old female xeroderma pigmentosum patient with recurrent basal cell carcinoma successfully treated by skin grafting. In that there is no cure for this disease, prevention and patient education is most important.

Bowel Perforation Due to Immobilization after Resurfacing Thumb with Anterolateral Thigh Free Flap in an Elderly Diabetic Woman

  • Park, Seong Hoon;Kim, Joo Hyun;Suh, In Suck;Kim, Kwang Yong;Jeong, Hii Sun
    • Archives of Reconstructive Microsurgery
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    • v.26 no.1
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    • pp.18-22
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    • 2017
  • Inevitable immobilization after surgery on lower extremities can induce chronic constipation. Elderly diabetic women usually express ambiguous gastrointestinal symptoms and signs. We present here a case of panperitonitis developed from severe fecal impaction in an elderly diabetic woman after hand reconstruction using material harvested from the lower extremities. A 68-year-old diabetic female underwent anterolateral thigh free flap and wound revision twice on the left thumb. Three weeks after surgery, she complained about mild abdominal pain though she had daily defecation. Despite encouraging ambulation, her compliance was low. Resection of the sigmoid colon and colostomy were performed after diagnosis with bowel perforation. However, the patient went into septic shock and died with multiorgan failure after the guardians issued a DNR (do not resuscitate) order. For preventing bowel perforation, increased uptake of dietary fiber and early ambulation postoperatively should be encouraged, after even hand surgeries.

Contribution of Perforator Flaps in the Flap Selection for Head and Neck Reconstruction (두경부 재건을 위한 피판 선택에서 천공지피판의 역할)

  • Kim, Jeong Tae
    • Korean Journal of Head & Neck Oncology
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    • v.35 no.1
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    • pp.1-11
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    • 2019
  • In head and neck reconstruction, microsurgeons are faced with various demands, such as thin resurfacing, or three-dimensional reconstruction, and therefore, conventional flap as well as perforator flaps are all useful for the functional and aesthetic reconstruction successfully. Among perforator flaps, the pros and cons of anterolateral thigh perforator flap(ALTp) and thoracodorsal perforator flap(TAp) is compared and selected depending on the surgeon's preference, recipient site condition or patient status. Both flaps can be elevated in a chimeric pattern by combining different aspects of tissue components. Customized or tailored reconstruction as well as 3 dimensional reconstructions are all available with perforator flaps and it is useful in head and neck reconstruction. The most outstanding update in head and neck reconstruction is the perforator based island flap (PBIF) compared to conventional flaps. The conventional local flap has evolved on behalf of the perforator concept and its design becomes more flexible and freestyle with less limitations. Actually, random pattern flap is now a misnomer and most conventional local flaps turn into PBIFs. Finally we can say all conventional donor site becomes universal, depending on the surgeons' preference or idea. Moreover, there is no more "flap of choice" and postoperative results are quite variable by surgeons' ability. Operative procedures and plans are very flexible to freestyle flap. With all these advantages, surgeons should be armed with both conventional and perforator concepts for solving any defects or problems.

Clinical Applications of a Non-ablative Fractional Dual Laser (1550/1927 nm)

  • Chang, Ho Sun;Lim, Nam Kyu
    • Medical Lasers
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    • v.9 no.2
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    • pp.110-118
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    • 2020
  • The non-ablative fractional dual laser is equipped with two types of lasers, 1550 nm and 1927 nm in one device, and was approved by the United States Food and Drug Administration in 2013. The advantages of the non-ablative fractional laser (NAFL) include fewer side effects such as erythema, edema, post-laser pigmentation, and scab formation. Thus, the NAFL is preferred by both practitioners and consumers because it is convenient and safe for use. The 1550 nm erbium glass and 1927 nm thulium lasers are representative NAFLs that have been developed separately and are often used as a single-wavelength laser with proven clinical efficacy in various indications. The 1550 nm wavelength laser penetrates the dermis layer and the 1927 nm wavelength laser is effective for epidermal lesions. Therefore, targeting the skin layer can be easily achieved with both the 1550 and 1927 nm lasers, respectively, or in combination. Clinically, the 1550 nm laser is effective in the treatment of mild to moderate sagging and wrinkles, scars, and resurfacing. The 1927 nm laser improves skin texture and treats skin pigmentation and wounds. It can also be used for drug delivery. The selection and utilization rate of NAFL has been increasing in recent times, due to changes in lifestyle patterns and the need for beauty treatments with fewer side effects and short downtime. In this study, we present a plan for safe and effective laser therapy through a review of literature. Clinical applications of the multifunctional NAFL are also described.

Core decompression for early-stage avascular necrosis of the humeral head: current concepts and techniques

  • Michael D. Scheidt;Saleh Aiyash;Dane Salazar;Nickolas Garbis
    • Clinics in Shoulder and Elbow
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    • v.26 no.2
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    • pp.191-204
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    • 2023
  • Avascular necrosis (AVN) of the humeral head is a rare, yet detrimental complication. Left untreated, humeral head AVN frequently progresses to subchondral fracturing and articular collapse. Cases of late-stage humeral head AVN commonly require invasive procedures including humeral head resurfacing, hemiarthroplasty, and total shoulder arthroplasty (TSA) to improve clinical outcomes. However, in cases of early-stage AVN, core decompression of the humeral head is a viable and efficacious short-term treatment option for patients with pre-collapse AVN of the humeral head to improve clinical outcomes and prevent disease progression. Several techniques have been described, however, a percutaneous, arthroscopic-assisted technique may allow for accurate staging and concomitant treatment of intraarticular pathology during surgery, although further long-term clinical studies are necessary to assess its overall outcomes compared with standard techniques. Biologic adjunctive treatments, including synthetic bone grafting, autologous mesenchymal stem cell/bone marrow grafts, and bone allografts are viable options for reducing the progression of AVN to further collapse in the short term, although long-term follow-up with sufficient study power is lacking in current clinical studies. Further long-term outcome studies are required to determine the longevity of core decompression as a conservative measure for early-stage AVN of the humeral head.

Near-infrared polarimetric study of near-Earth object 252P/LINEAR: An implication of scattered light from the evolved dust particles

  • Kwon, Yuna G.;Ishiguro, Masateru;Kwon, Jungmi;Kuroda, Daisuke;Im, Myungshin;Choi, Changsu;Tamura, Motohide;Nagayama, Takahiro;Kawai, Nobuyuki;Watanabe, Jun-Ichi
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.44.2-44.2
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    • 2019
  • Comets, one of the least-altered leftovers from the nascent solar system, have probably preserved the primitive structure inside, whereas their surfaces become modified from the initial states after repetitive orbital revolutions around the Sun. Resurfacing makes the surface drier and more consolidated than the bulk nuclei, creating inert refractory dust layer ("dust mantle"). Near-infrared (NIR; 1.25-2.25 m) polarimetry is theoretically expected to maximize contrast of the porosity between inner fresh and evolved dust particles, by harboring more dust constituents in the single wavelength than the optical; thus, intensifies electromagnetic interaction in dust aggregates. Despite such an advantage, only a few studies have been made in this approach mainly due to the limited accessibility of available facilities. Herein, we present our new multi-band NIR polarimetric study of near-Earth object 252P/LINEAR over 12 days near perihelion, together with the results of optical (0.48-0.80m) imaging observations and backward dynamical simulation of the comet. Based on the results, we will characterize the dust properties of the comet and discuss the possible environmental (temperature and UV radiation) effects that could produce the observed phenomena.

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COST BENEFIT ANALYSIS OF HIGHWAY SYSTEMS

  • Darren Thompson;Don Chen;Nick Walker;Neil Mastin
    • International conference on construction engineering and project management
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    • 2013.01a
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    • pp.494-496
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    • 2013
  • Cost-Benefit Analysis (CBA) is a systematic optimization process that allows users to compare different alternatives and to determine if a project is a solid investment. Many state DOTs have included CBA in their pavement management systems (PMSs) to help allocate state funds for maintenance, rehabilitation, resurfacing, and reconstruction of pavements. In a typical CBA, each pavement type has an assigned weight factor which represents the level of importance of this pavement type. To conduct an accurate CBA, it is essential to select appropriate weight factors. Arbitrarily assigning weights factors to pavements can lead to biased and inaccurate funding allocation decisions. The purpose for this paper is to outline a method to develop an ideal set of weight factors that can be utilized to conduct more accurate CBA. To this end, a matrix of all possible weight factors sets was developed. CBA was conducted for each set of weight factors to obtain a population of possible optimization solutions. Then a regression analysis was performed to establish the relationship between benefit and weight factors. Finally, a multi-objective genetic algorithm was applied to select the optimal set of weight factors. The findings from this study can be used by state DOTs to strategically manage their roadway systems in a cost effective manner.

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