• Computational Structural Engineering
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• v.10 no.3
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• pp.241-250
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• 1997

The strain localization of concrete is a phenomenon such that the deformation of concrete is localized in finite region along with softening behavior. The objective of this paper is to develop a plasticity and damage algorithm for the finite element analysis of the strain-localization in concrete. In this paper, concrete member under strain localization is modeled with localized zone and non-localized zone. For modeling of the localized zone in concrete under strain localization, a general Drucker-Prager failure criterion by which the nonlinear strain softening behavior of concrete after peak-stress can be considered is introduced in a thermodynamic formulation of the classical plasticity model. The return-mapping algorithm is used for the integration of the elasto-plastic rate equation and the consistent tangent modulus is also derived. For the modeling of non-localized zone in concrete under strain localization, a consistent nonlinear elastic-damage algorithm is developed by modifying the free energy in thermodynamics. Using finite element program implemented with the developed algorithm, strain localization behaviors for concrete specimens under compression are simulated.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.4
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• pp.471-476
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• 2015

Purpose: We have analyzed the transmittance distribution of various ocular lenses using local transmittance microscope to investigate the optical homogeneity of the lens. Methods: The local transmittance of the laser which is focused on the surface of the spectacle lens was measured by using the photo-detector, lock-in amplifier and motorized-stage. 25 multi-coated lenses with non-tinted of 5 groups and 45 multicoated lenses with tinted of 9 groups were analyzed as a sample respectively. Results: Average and deviation of local transmittance for nontinted lenses were measured almost uniformly with various refractive index and coating. However, deviation of transmittance of for tinted lenses was analyzed as about 3.7 times larger than that of non-tinted lenses. Inhomogeneity of local transmittance of for tinted lenses was also analyzed as about 3.1 times larger than that of non-tinted lenses. Conclusions: We could analyze that standard deviation of transmittance and inhomogeneity of local transmittance of for tinted lenses is larger than that of non-tinted lenses using the local transmittance microscope. These analysis using local transmittance microscope can be utilized as a way to evaluate lens performance and improve optical homogeneity.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.3
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• pp.295-300
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• 2009

Statement of problem: As the number of elders is growing with the advancement of medicine, partially or fully edentulous patients have increased. Medically compromised conditions are common in the older population so that it should be taken into account in prosthetic treatment planning as well as their economic conditions. In the older patients, removable prosthesis has been preferred to implant prosthesis. However, cast metal based removable partial dentures also has several limitations. Purpose: In this report, we present several cases of Valplast$^{(R)}$ flexible denture which were fabricated in patients who had medically compromised conditions or whose remaining teeth showed a relatively poor prognosis. Results & Conclusion: This article describes an alternative treatment for a partially edentulous patient with mouth opening limitation, after cancer surgery, compromised general condition and questionable remaining teeth. In these patients, Valplast$^{(R)}$ flexible denture was used because of its unique characteristics and the results were all satisfactory. Patients had 1-2 check-up and there were no postoperative pain or fracture of denture up to now.

• Journal of Life Science
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• v.2 no.2
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• pp.97-107
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• 1992

Strichartz and Richie have suggested that the mechanism of sodium donductance block of local anesthetics involves their interaction with a specific binding site within the sodium channel. However, there is evidence that local anesthetics can interact electrostatically with membrane proteins as well as membrane lipids. Whether or not all actions of local anesthetics are mediated by common site remains unclear. Thus, it can not be ruled out that local anesthetics concurrently interact with neuronal membrane lipids since sodium channels were found to be tightly associated with membrane lipids through covalent or noncovalent bonds. In summary, it is strongly postulated that local anesthetics, in addition to their direct interaction with sodium channels, concurrently interact with membrane lipids, fluidize the membrane, and thus induce conformational changes of sodium channels, which are known to be tightly associated with membrane lipids.

• Journal of the Korean Arthroscopy Society
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• v.15 no.2
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• pp.113-116
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• 2011

Reports of localized giant cell tumor arising from the posterior cruciate ligament are rare, and its recurrence rate after incomplete excision. We experienced a case of localized giant cell tumor arising from the posterior cruciate ligament that were excised arthroscopically with transseptal approach and pathologically confirmed. The patient showed good clinical result for one year after operation. So we report a case with a review of the literatures.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.5
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• pp.44-54
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• 2003

The experiments are performed to evaluate mechanical properties about foam and face materials of sandwich beams. These results are applied to the flexural wrinkling estimation of sandwich beam. The 3 point bending test shows that it is reasonable to include pre-buckling behavior in flexural wrinkling analysis, which is closer to experimental result. It is also conducted to survey the wrinkling behavior.

• Magazine of the Korea Concrete Institute
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• v.8 no.2
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• pp.129-138
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• 1996

Localization of concrete is a phenomenon such that the deformation of concrete is localized in finite region with softening behavior and it governs ultimate load of concrete. In this Paper, concrete under strain localization was modeled with localization region and non-localization region and lc~calization behavior was formulated based on averaging concept of heterogeneous material. By using the formulation, the localization phenomena of concrete under uniaxial loadings were well predicted. The analytical results show that size of localization region of concrete under uniaxial compression is three times of maximum aggregate size and the size effect of concrete is well predicted. The use of tension-softening curve obtained from direct tension test is suitable for well prediction of localization of concrete under uniaxial tension.

• Proceedings of the KSMRM Conference
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• 1997.10a
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• pp.52-52
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• 1997

• Radiation Oncology Journal
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• v.10 no.2
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• pp.213-217
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• 1992

Locally advanced cervical carcinoma has shown high rate of local failure and poor survival rate despite the advances in modern radiation therapy techniques. Combination of chemotherapy and radiation therapy demonstrated benefit in improving local control and possibly the overall survival. Twelve patients with advanced stages (Figo stage III, IV) or 11b with bulky tumors (>5 cm in diameter) were treated with combination of radiation therapy and concurrent weekly cisplatin between May of 1988 and September of 1991 at Inje University Paik Hospital. Cisplatin was administered in bolus injections of 50 mg at weekly intervals during the courses of radiation therapy. Median follow-up period was 34 months with ranges from 3 to 53 months. Eleven patients were evaluable for the estimation of response. Response was noted in all the 11 patients: complete response (CR) in 7 ($64\%$), partial response (PR) in 4 ($36\%$). Of the 7 patients with CR, all maintained local control, whereas only 1 of 4 with PR showed local control. Six of 7 with CR are alive disease free on the completion of follow-up. Eight of 11 patients ($73\%$) maintained local control in the pelvis. The median survival for CR patient is 27 months and 9 months for the PR patients. Analysis of survival by stage shows 11 b 4/5, III 2/3 and IV 1/3. Overall survival rate was $61\%$. Three patients recurred: 1 at local, 1 in distant site and 1 with local and distant site. Toxicity for the combination therapy was not excessive. These results are preliminary, but definitely encouraging in view of markedly improved response rate compared with the results of historical control group.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.2
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• pp.140-145
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• 2024

Removable partial denture wearers are exposed to the risks that remaining teeth get damaged by caries, attritions, erosion, and fracture. In the case of damaged abutment tooth which should fit to Removable partial denture (RPD), the fabrication of surveyed crown is followed by the making of RPD. However, making new denture takes a long time, and needs several processes and costs. Also, patients should get used to new denture. If other abutment teeth and edentulous ridges provide the existing denture with support, retention, and stability, use of existing denture is considered clinically acceptable. In this situation, fabricating retrofit crowns to an existing removable partial denture makes patient use existing denture, cuts costs, and reduces discomfort. In this case, severely worn teeth were restored using monolithic zirconia crown which fit to an existing removable partial denture by CAD-CAM. Moreover, support, retention, and stability of the denture were improved, and both doctor and patient were satisfied with the result.