• Journal of Korean Foot and Ankle Society
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• v.8 no.1
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• pp.64-70
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• 2004

Purpose: We compared the result of a proximal metatarsal closed wedge osteotomy and soft tissue procedure with a modified chevron osteotomy and soft tissue procedure in the treatment of hallux valgus. Materials and Methods: Between March 1999 and February 2003, we performed proximal metatarsal closed wedge osteotomy and soft tissue procedure on 17 feet (12 patients), and modified chevron osteotomy and soft tissue procedure on 12 feet (9 patients). Results: According to Mayo clinic forefoot scoring system (FFSS), group 1, with proximal metatarsal closed wedge osteotomy, shows 67.2 points postoperatively and group 2, with modified chevron osteotomy, shows 68.5 points postoperatively. In group 1, the average correction of hallux valgus angle and intermetatarsal angle was 20.8 degrees and 4.8 degrees, respectively. In group 2, the average correction of hallux valgus angle and intermetatarsal angle was 19.9 degrees and 4.7 degrees, respectively. The average shortening was 3.15 mm in group 1 and 1.38 mm in group 2. Conclusion: We obtained relatively good clinical and radiographic result in this study. The effect on shortening of the first metatarsal was greater in the proximal metatarsal closed wedge osteotomy than modified chevron osteotomy, but the metatarsal shortening did not related with metatarsalgia. So, both techniques seems optimal surgical treatment for hallux valgus deformity.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.04a
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• pp.19-24
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• 1994

Four types of horizontal joint were tested to investigate the difference with regards to the compressive behavior and strength. These include wedge-type joints (i)with and (ii)without transverse reinforcement against splitting failure of the panel concrete, and wedge-type joints (iii)with different widths of joint concrete (6cm vs 8cm) and (iv)closed platform joint. It was shown that the compressive strength of wedge-type joint is about 10% higher than that of closed-type (platform) joint. But the effect of transverse reinforcement and joint concrete widths on the strength of the joints turned out be negligible. Also, the moduli of elasticity in panel and joint are compared and the equivalent moduli of the whole wall are derived.

• Knee surgery & related research
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• v.30 no.4
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• pp.293-302
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• 2018

Purpose: High tibial valgus osteotomy (HTO) is a well-established surgical procedure for patients with medial compartment osteoarthritis (OA) of the knee. The hybrid closed-wedge HTO (CWHTO) procedure permits extensive correction in patients with severe deformities or patellofemoral joint OA. The aim of this study was to report the short-term results in a consecutive series of patients treated with hybrid CWHTO. Materials and Methods: We retrospectively evaluated the clinical outcomes and radiographic parameters in 29 consecutive knees that underwent hybrid CWTHO to correct medial compartment OA at an average follow-up of 52.6 months. Clinical outcomes were assessed using the Lysholm score and knee scoring system of the Japanese Orthopedic Association (JOA). The Kellgren-Lawrence grading system and pre- and postoperative mechanical axis (MA), femorotibial angle (FTA), posterior tibial slope, and patella height were assessed. Results: The FTA and MA significantly changed from $180.7^{\circ}$ to $170.4^{\circ}$ and from $22.0^{\circ}$ to $60.2^{\circ}$, respectively. No significant differences were observed between the mean pre- and postoperative posterior tibial slope, Insall-Salvati ratio, or Caton-Deschamps index. The postoperative JOA and Lysholm scores significantly improved from 76.7 to 95.8 and from 58.8 to 90.2, respectively. Conclusions: Satisfactory outcomes can be achieved with hybrid CWHTO in patients with medial OA.

• Annals of Clinical Neurophysiology
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• v.20 no.1
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• pp.31-35
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• 2018

Background: Although postural instability is one of the major symptoms of Parkinson's disease (PD), dopaminergic treatment is ineffective for treating postural instability. Recent reports have shown that somatosensory deficit is associated with postural instability, and that somatosensory input improved postural instability. The purpose of this study is to evaluate the effects of lateral wedges for quiet standing postural control in people with PD. Methods: Twenty-two patients who were diagnosed with PD were enrolled in this study. The participants stood on a force plate under two conditions (wedge and no wedge) with or without having their eyes open or closed. The center of pressure (COP) range and velocity were analyzed using a two-way repeated-measures analysis of variance. Results: The range and velocity of COP in the anterioposterior and mediolateral (ML) directions were significantly improved after the patients stood on the lateral wedge with their eyes closed (p < 0.05). The range in ML direction and velocity in both directions of COP were significantly decreased when their eyes were open (p < 0.05). Conclusions: Regardless of vision, standing on lateral wedges improved postural sway in people with PD.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.180-183
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• 2005

The purpose of this study is to evaluate a closed-die forging method for large crank throw using analytical and numerical approaches. A closed-die forging equipment with wedge and links was proposed to forge large crank throw using kinematic analysis. The minimum press capacity for the closed-die forging was established using the comprehensive FEA.

• Journal of the Korean Mathematical Society
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• v.45 no.1
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• pp.151-161
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• 2008

We prove that a countably condensing operator defined on a closed wedge in a Banach space has a fixed point if it is strictly quasibounded, by using an index theory for such operators. From this, the existence of eigenvalues and surjectivity are deduced.

• The Academic Congress of Korean Shoulder and Elbow Society
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• 2009.03a
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• pp.209-209
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• 2009

• Journal of applied mathematics & informatics
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• v.26 no.3_4
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• pp.673-678
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• 2008

Let $W_{\alpha}$, be a recursively generated quadratically hyponormal weighted shift with a weight sequence ${\alpha}$ : 1, (1, $\sqrt{x}$, $\sqrt{y}$)$^{\wedge}$. In [4] Curto-Jung showed that R = {(x,y) : $W_{1,\;(1,\;{\sqrt{x}},\;{\sqrt{y}})^{\wedge}}$ is quadratically hyponormal} is a closed convex with nonempty interior, which guarantees that there are a lot of quadratically hyponormal weighted shifts with first two equal weights. They suggested a problem computing expressions of certain extremal points of R. In this note we obtain a partial answer of their extremal problem.

• Journal of the Society of Naval Architects of Korea
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• v.54 no.4
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• pp.321-328
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• 2017

In practice, cavitation phenomena occur in unbounded flows. However, the wall effect is unavoidable during experiments at a closed section such as a cavitation tunnel. Especially, supercavity generated behind a cavitator is relatively large and thick, so that geometric and dynamic characteristics of the cavity are affected by the tunnel wall. In order to apply experimental results into the unbounded flow field, physical correlations are necessary. In this paper, we proposed an image method based on a potential flow to simulate the wall effect. Considering two-dimensional wedge-shaped bodies, configurations and drag characteristics of the cavity were examined according to the distance ratio to the wall surface. The results were compared and verified with existing theoretical and experimental results.

• Journal of radiological science and technology
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• v.37 no.4
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• pp.341-348
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• 2014

Wedge filter could use to increase the dose distribution at the hot dose regions. We evaluated dose discrepancy at surface and build region in the infield and outfield that Metal Wedge (MW) and Enhance Dynamic Wedge (EDW) were interact with photon. In this paper, we used Gafchromic EBT3 film that had excellent spatial resolution, composed the water equivalent materials and changed the optical density without development. The set up conditions of linear accelerator were fixed 6 MV photon, 100 cm SSD, $10{\times}10cm^2$ field size and were irradiated 400 cGy at Dmax. The dose distribution and absorbed dose were evaluated when we compared the open field with $15^{\circ}$, $30^{\circ}$, $45^{\circ}$ metal wedge and enhanced dynamic wedge. A $15^{\circ}$ metal wedge could increase the surface and build up region dose than using a $15^{\circ}$ enhanced dynamic wedge. A $30^{\circ}$ metal wedge could decrease the surface and build up region dose than using a $30^{\circ}$ enhanced dynamic wedge. A $45^{\circ}$ metal wedge could decrease by large deviation the surface and build up region dose than using a $15^{\circ}$ enhanced dynamic wedge. The dose of penumbra region at outfield were increased on the thick side but were decreased on the thin side. It could be decrease the surface dose and build up region dose, if the metal wedge filters were properly used to make a good dose distribution and not closed the distance of surface.