• Korean Journal of Mathematics
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• v.13 no.2
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• pp.235-239
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• 2005

In this paper we study some characterizations of proximal, distal and almost one to one homomorphisms of flows. In particular we show that if the almost one to one proximal extension of a minimal flow is weakly almost periodic, then it is minimal.

• Korean Journal of Mathematics
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• v.12 no.2
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• pp.171-175
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• 2004

The purpose of this paper is to investigate some lifting properties of homomorphisms of flows. It is shown that an almost one to one extension of a minimal proximal flow is proximal. It is also shown that a distal extension of a pointwise almost periodic flow is pointwise almost periodic.

• Archives of Plastic Surgery
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• v.46 no.1
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• pp.84-87
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• 2019

With the recent development in microsurgery, the use of a perforator flap has been widely implemented. If the length of the ALT flap pedicle is insufficient despite adequate preoperative planning, pedicle length extension is necessary. We planned for a reverse ALT free flap using the distal vessel of the descending branch for pedicle length extension in the case of ALT perforator branch originating from the proximal portion of the descending branch. For the management of venous congestion, the distal venae comitantes were anastomosed to the proximal venous stump in an antegrade manner, successfully resolving the venous congestion. Modified reverse-flow ALT free flap, wherein the venae comitantes are anastomosed to the proximal vein stump, is a good option that allows for relatively simple pedicle extension within the same operative field when securing an adequate pedicle length is difficult because of the origin of the perforator from the proximal descending branch, unlike the initial surgical plan.

• Korean Journal of Mathematics
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• v.18 no.1
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• pp.79-86
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• 2010

In this paper we give some results on homomorphisms of flows. In particular, we investigate the sufficient conditions for the homomorphism of flows to be its own regularizer.

• Archives of Plastic Surgery
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• v.33 no.4
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• pp.480-484
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• 2006

Purpose: A lot of surgical techniques were tried to correct extension lag of distal interphalangeal joint. Spiral oblique retinacular ligament reconstruction is the one of correction techniques. Methods: From January 2004 to January 2005, a total of 13 extension lag of distal interphalangeal joint corrections were performed using spiral oblique retinacular ligament reconstruction for 11 patients. After dorsal incision exposing from base of distal phalanx to proximal phalanx, the new ligament(half of lateral band or graft tendon) lies distally at the dorsum of the distal phalanx and passes volarly and proximally along the side of the middle phalanx and anterior and obliquely across the front of the proximal interphalangeal joint to the opposite side of the digit at the proximal phalanx. Results: 5 of 6 mallet finger deformities and 7 swan neck deformities were corrected, which were both extension lag of distal interphalangeal joint and hyperextension of proximal interphalangeal joint. Conclusion: As a result, spiral oblique retinacular ligament reconstruction is an effective and recommendable method for correction of mallet finger deformity and swan neck deformity.

• Journal of the Chungcheong Mathematical Society
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• v.37 no.1
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• pp.41-55
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• 2024

The nonconvex and nonsmooth optimization problem has been widely applicable in image processing and machine learning. In this paper, we propose an extension of the proximal iteratively reweighted ℓ₁ algorithm for nonconvex and nonsmooth minmization problem. We assume the co-coerciveness of a term of objective function instead of Lipschitz gradient condition, which is generalized property of Lipschitz continuity. We prove the global convergence of the proposed algorithm. Numerical results show that the proposed algorithm converges faster than original proximal iteratively reweighed algorithm and existing algorithms.

• Journal of Korean Neurosurgical Society
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• v.62 no.5
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• pp.603-609
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• 2019

Objective : The purpose of this retrospective study was to determine which of the proximal adjacent segment disease (ASD) and distal ASD was more prevalent and what parameters is more related to ASD in proximal levels and distal levels after more than 2 levels fusions. Methods : The medical records were reviewed retrospectively for 856 cases. A total of 66 cases of ASD were enrolled. On preop magnetic resonance imaging, disc degeneration was measured at the upper and lower parts of surgically treated levels and confirmed by the commonly used Pfirrmann grade. Segmental flexibility in sagittal plane was embodied in segment range of motion (ROM) obtained through flexion and extension X-ray before surgery. Coronal angle was recorded as methods Cobb's angle including fusion levels preoperatively. For the comparison of categorical variables between two independent groups, the chi-square test and Fisher exact test were performed. Results : Proximal ASD and distal ASD were 37/856 (4.32%) and 29/856 (3.39%), respectively. The incidence of proximal ASD was relatively high but insignificant differences. In comparison between ASD group and non ASD group, proximal Pfirmman was higher in proximal ASD and distal Pfirmman was higher in distal ASD group (p=0.005, p<0.008, respectively). However, in the ROM, proximal ROM was higher in proximal ASD, but distal ROM was not different between the two groups (p<0.0001, p=0.995, respectively). Coronal angle was not quite different in both groups (p=0.846). Conclusion : In spite of higher frequency in ASD in proximal level in spinal fusion, it is not clear that incidence of ASD in proximal level is not higher than that of distal ASD group in more than 2 level thoracolumbar fusions. Not only Pfirrmann grade but also proximal segmental ROM is risk factor for predicting the occurrence of ASD in patients more than 2 level of thoracolumbar spine fusion operation excluding L5S1.

• The Journal of the Korean bone and joint tumor society
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• v.2 no.1
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• pp.8-17
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• 1996

The purpose of this study is a comparative evaluation of range motion, especially extension deficit between the group of total patellectomy and that of intact patella, after reconstruction of the patellar tendon in the prosthetic replacement of a proximal tibia. Between 1990 and 1994, 15 patients who had a primary malignancy on proximal tibia were operated on. All patients were evaluated clinically and radiographically. Two patients were excluded because one had a deep infection treated with arthrodesis of the knee and the other was a composite allograft. The mean follow-up of the 13 patients was 27 months(15-47), including 10 osteosarcomas, 1 chondrosarcoma, 1 malignant fibrous histiocytoma and 1 malignant giant cell tumor. Eleven patients had a resection of the proximal tibia and 2 had an extracapsular total knee resection with distal femur. Reconstruction of the defect was done in 8 cases with a custom-made Link Endo-Model Total Rotation Knee Joint Prosthesis, and in 5 with How Medica Modular Resection System (HMRS). We used two methods to reconstruct the ligamentum patellae. Fixation of the patellar tendon to the prosthesis only with suturing and/or stapling(group SS) was done in 7. Transposition of gastrocnemius muscle to enhance fixation and to cover the prosthesis(group TG) was done in 6. Regardless of fixation methods, total patellectomy was done in 5 either to lengthen the patellar tendon or to make primary skin closure easier or for both. In 8 cases, patella was left intact or resurfaced with polyethylene prosthesis. Active extension was measured while the patient was in a sitting position. There is no statistically meaningful difference in terms of extension deficit (Wilcoxon rank test, p=0.8800) between patellectomy group and intact patella group, and between group of fixation only with suturing and that of gastrocnemius transposition. Two cases of extension deficit over 30 degree were seen in group SS and in the group of intact patella. Conclusively, total patellectomy could be an option without increasing the risk of extension deficit when primary skin closure is difficult or patellar tendon is a little bit short to be fixed. There is no rating in the Enneking system of functional evaluation that this finding into consideration.

• Imaging Science in Dentistry
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• v.44 no.3
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• pp.199-205
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• 2014

Purpose: This study aimed to investigate the effect of changing the kilovoltage peak (kVp) on the radiographic assessment of dental caries. Materials and Methods: Seventy-five extracted posterior teeth with proximal caries or apparently sound proximal surfaces were radiographed with conventional E-speed films and a photostimulable phosphor system using 60 kVp and 70 kVp for the caries assessment. The images were evaluated by three oral radiologists and compared with the results of the stereomicroscope analysis. Results: No statistically significant difference was found between 60 kVp and 70 kVp for the caries detection, determination of caries extension into dentin, and caries severity in either the conventional or the digital images. Good to very good inter-observer and intra-observer agreements were found for both kilovoltage values on the conventional and digital images. Conclusion: Changing the kilovoltage between 60 kVp and 70 kVp had no obvious effect on the detection of proximal caries or determination of its extension or severity.

• Communications of the Korean Mathematical Society
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• v.23 no.3
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• pp.453-459
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• 2008

We introduce a concept of continuous homomorphisms between Csaszar frames and show that the Cauchy completion in CsFrm gives rise to a coreflection in the category PCsFrm (resp. UCsFrm) consisting of proximal Csaszar frames and uniform continuous homomor-phisms (resp. uniform Csaszar frames and uniform continuous homomor-phisms).