• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.2
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• pp.213-221
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• 2011

In this study, we discussed the weight reducing of a urban railway-car body, in particular, of the Korean EMU, by optimizing topology and size of aluminum extrusion profiles. The heaviest parts of aluminum railway-car bodies, i.e., the base plate of underframe and side panels of side frame composed of double skin structures are considered for optimization. Topology optimization process is applied to obtain get an optimized rib structure for the base plate. The thickness of ribs and plates of the topologically optimized base plate and the existing side panel are also optimized by employing the size optimization process. The results are verified by comparing the maximum von Mises stresses and maximum deformation in the case of the existing design with those in the case of the optimized design. It is shown that the weight of a base plate and side panel can be reduced by 12% and that the weight of the whole car body can be reduced by 8.5%.

• Archives of Reconstructive Microsurgery
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• v.14 no.2
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• pp.152-156
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• 2005

Purpose: We reconstructed the thumb with groin flap combined with secondary heterodigital neurovascular island flap and report our 6 cases. Materials and Methods: Between March 2003 and August 2004, 6 degloving thumbs or amputation of thumbs were reconstructed with groin flap combined with secondary heterodigital neurovascular island flap. There ware 4 men and 2 women, and mean age was 42.2 years. The following parameters were evaluated. Results: Recipient thumb was no limitation of apposition. but flexion contracture of interphalangeal joint was about 10 degree in two cases. Average grip power were 80% and average pinch power were 70% that of the normal thumb. The two point discrimination was average 10.5 mm and double sensibility in 2 cases. 2 patients have cold intolerance. Neuroma formation was not made. Cosmetic results as judged by patients were that 4 cases are good and 2 cases are fair. Conclusion: If massive skin defect after degloving thumb or amputation of thumb are present, we consider the numerous methods for reconstruction of thumb. This surgical procedure is good methods because of it's pliability, sensation, satisfactory functional results but major disadvantage are the staged operation and cosmetic effect of the absence of thumb nail.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3307-3314
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• 2012

The annual energy demand of the standard rural house models was analyzed using the DesignBuilder. Indoor temperature set-point, U-value of outer wall, type of window, and degree of ventilation were selected as simulation parameters. In all the simulation cases, heating energy demand was higher than cooling energy demand regardless of the building size. When the lower U-value of the outer wall was applied to account for the thicker insulation layer, heating energy demand was decreased while cooling energy demand was increased. However, it is better to reduce the area of outer wall which is directly exposed to outdoor air because reducing the U-value of the outer wall is not effective in decreasing heating energy demand. Among the four different window types, the double skin window is most favorable because heating energy demand is the lowest. For a fixed infiltration rate, higher ventilation rate resulted in an increased heating energy demand and had minor impact on cooling energy demand. As long as the indoor air quality is acceptable, lower ventilation rate is favorable to reduce the annual energy demand.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.1
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• pp.1-9
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• 1995

1, 25(OH)2-23ene-D3 is a novel vitamine D3 analog which has a double bond between C-23 and C-24. We describe the effects of this analog on cell differentiation and cell proliferation in vitro using the human histiocytic lymphoma cell line U937, and on calcium metabolism in rats in vivo. In the present investigation 1, 25(OH)2-23ene-D3 was compared to the natural metabolite of vitamin D3, 1$\alpha$, 25-dihydroxycholecalciferol[1, 25(OH)2-23ene-D3 was more potent than 1, 25(OH)2-23ene-D3 for inhibition of proliferation and induction of differentiation of U937 cells. Especially, its effect on induction of differentiation, as measured by superoxide production and nonspecific esterase(NSE) activity, was about 20-fold more potent that 1, 25(OH)2-23ene-D3. This analog morphologically and functionally differentiated U937 cells to monocyte-macrophage phenotype showing a decrease of N/C ratio in Giemsa staining and the increase of adherence ability to surface. Intraperitoneal administration of 1, 25(OH)2-23ene-D3 to rats showed that the compound had at least 50 times less activity than 1, 25(OH)2-23ene-D3 in causing hypercalcemia and hypercalciuria. The strong direct effects of 1, 25(OH)2-23ene-D3 on cell proliferation and cell differentiation, coupled with its decreased activity of calcium metabolism make this compound an interesting candidate for clinical studies including patients with leukemia, as well as several skin disorders, such as psoriasis.

• Steel and Composite Structures
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• v.30 no.5
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• pp.405-416
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• 2019

Profiled composite slab has been widely used in civil engineering due to its structural merits. The extension of this concept to the bearing wall forms the profiled composite wall, which consists of two external profiled steel plates and infill concrete. This paper investigates the structural behavior of this type of wall under axial compression. A series of compression tests on profiled composite walls consisting of varied types of profiled steel plate and edge confinement have been carried out. The test results are evaluated in terms of failure modes, load-axial displacement curves, strength index, ductility ratio, and load-strain response. It is found that the type of profiled steel plate has influence on the axial capacity and strength index, while edge confinement affects the failure mode and ductility. The test data are compared with the predictions by modern codes such as AISC 360, BS EN 1994-1-1, and CECS 159. It shows that BS EN 1994-1-1 and CECS 159 significantly overestimate the actual compressive capacity of profiled composite walls, while AISC 360 offers reasonable predictions. A method is then proposed, which takes into account the local buckling of profiled steel plates and the reduction in the concrete resistance due to profiling. The predictions show good correlation with the test results.

• Journal of the Korean Society of Industry Convergence
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• v.21 no.6
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• pp.337-344
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• 2018

Food irradiation is important not only in ensuring safety but also improving antioxidant activity of peaches. Our objective was to establish the best irradiation treatment for peaches by calculating dose distribution using Monte Carlo simulation. 3-D geometry and component densities of peaches, extracted from CT scan, were entered into MCNP to obtain simulated dose distribution. Radiation energies for electron beam were 1.35 MeV (low energy) and 10 MeV (high energy). Co (1.25 MeV) and the Husman irradiator, containing three sealed Cs source rods in an annular array, were used for gamma irradiation. At 1.35 MeV electron beam simulation, electrons penetrated well beyond the peach skin, enough for surface treatment for microorganisms and allergens. At 10 MeV electron beam simulation, for top-beam only treatment, doses at the core were the highest and for double beam treatment, the electron energy was absorbed by the entire sample. At Co source, the radiation doses were presented on the whole area. At Cs source, the dose uniformity ratios were 2.78 for one source and 1.48 for three ones at 120 degrees interval. Proper control of irradiation treatment is critical to establish confidence in the irradiation process.

• Journal of the Korean Orthopaedic Association
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• v.56 no.2
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• pp.168-172
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• 2021

Acquired digital fibrokeratoma is very a rare, benign, fibrous, and hyperkeratotic skin tumor that develops most frequently on the finger or toe. The tumor usually occurs in adults as a solitary, dome-shaped lesion. Sometimes, it appears as a rudimentary supernumerary digit and may be misdiagnosed as an accessory nail (double nail) or verruca vulgaris. The pathophysiology of an acquired digital fibrokeratoma is unknown. On the other hand, trauma has often been proposed as a predisposing factor for an acquired type of digital fibrokeratoma. This paper reports a case of trauma-related acquired digital fibrokeratoma presenting as a supernumerary digit and nail in a 36-year-old male. This case is presented with a 0.5 cm×0.4 cm×1.3 cm sized, firm, hyperkeratotic, protruding mass over the left second finger nail.

• The Korean Journal of Pain
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• v.33 no.4
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• pp.378-385
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• 2020

Background: The thoracic paravertebral block is an effective analgesic technique for postoperative pain management after breast surgery. The ultrasound-guided retrolaminar block (RLB) is a safer alternative to conventional paravertebral block. Thus, we assessed the analgesic efficacy of ultrasound-guided RLB for postoperative pain management after breast surgery. Methods: Patients requiring breast surgery were randomly allocated to group C (retrolaminar injection with saline) and group R (RLB with local anesthetic mixture). The RLB was performed at the level of T3 with local anesthetic mixture (0.75% ropivacaine 20 mL + 2% lidocaine 10 mL) under general anesthesia before the skin incision. The primary outcome was cumulative morphine consumption using intravenous patient-controlled analgesia (IV-PCA) at 24 hour postoperatively. The secondary outcomes were the visual analogue scale (VAS) scores at 1, 6, 24, and 48 hour postoperatively and the occurrence of adverse events and patient satisfaction after the surgery. Results: Forty-six patients were included, 24 in group C and 22 in group R. The cumulative morphine consumption using IV-PCA did not differ between the two groups (P = 0.631). The intraoperative use of remifentanil was higher in group C than in group R (P = 0.025). The resting and coughing VAS scores at 1 hour postoperatively were higher in group R than in group C (P = 0.011, P = 0.004). The incidence of adverse events and patient satisfaction was not significantly different between the two groups. Conclusions: A single injection of ultrasound-guided RLB did not reduce postoperative analgesic requirements following breast surgery.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.1
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• pp.92-97
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• 2005

Inhibition of inflammatory response, acceleration of basal cell growth, and balanced synthesis of extracellular matrix (ECM) are important in healing of cutaneous open wounds. In order to evaluate the healing effects of water extracts of Radix Astragali (the root of Astragalus membranaceus (Fisch.)) on open wound at early stage, the experimental open wounds were generated on the dorsal sides of SD rats under anesthesia. The boiled-water extracts of Radix Astragali $(100{\mu}l)$, soaked into an occlusive film dressing were applied once a day for eleven consecutive days. The healing process was assessed by measuring macroscopic appearance and wound areas of the open wounds. The molecular aspects of healing process by Radix Astragali extracts were also investigated by Hematoxylin-Eosin (H-E) double staining and immunohistological staining of collagen type I in the healed skin area, implying cell density and linear alignment of the granulation tissue, and ECM synthesis and its remodeling, respectively. The Astragali radix extracts were found to significantly accelerate the cutaneous wound healing by suppressing the inflammation and stimulating the basal cell growth in wounded area, as compared to epidermal growth factor (EGF).

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.712-716
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• 2010

Purpose: Extensive lumbosacral defects after removal of spinal tumors have a high risk of wound healing problems. Therefore it is an effective reconstructive strategy to provide preemptive soft tissue coverage at the time of initial spinal surgery, especially when there is an instrument exposure. For soft tissue reconstruction of a lumbosacral defect, a variation of the gluteal flap is the first-line choice. However, the musculocutaneous flap or muscle flap that is conventionally used, has many disadvantages. It damages gluteus muscle and causes functional disturbance in ambulation, has a short pedicle which limits areas of coverage, and can damage perforators, limiting further surgery that is usually necessary in spinal tumor patients. In this article, we present the superior gluteal artery perforator turn-over flap that reconstructs complex lumbosacral defects successfully, especially one that has instrument exposure, without damaging the ambulatory function of the patient. Methods: A 67 year old man presented with sacral sarcoma. Sacralectomy with L5 corpectomy was performed and resulted in a $15{\times}8\;cm$ sized complex soft tissue defect in the lumbosacral area. There was no defect in the skin. Sacral stabilization with alloplastic fibular bone graft and reconstruction plate was done and the instruments were exposed through the wound. A $18{\times}8\;cm$ sized superior gluteal artery perforator flap was designed based on the superior gluteal artery perforator and deepithelized. It was turned over 180 degrees into the lumbosacral dead space. Soft tissue from both sides of the wound was approximated over the flap and this provided in double padding over the instrument. Results: No complications such as hematoma, flap necrosis, or infection occurred. Until three months after the resection, functional disturbances in walking were not observed. The postoperative magnetic resonance imaging scan shows the flap volume was well maintained over the instrument. Conclusion: This superior gluteal artery perforator turn-over flap, a modification of the conventional superior gluteal artery perforator flap, is a simple method that enabled the successful reconstruction of a lumbosacral defect with instrument exposure without affecting ambulatory function.