• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.11
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• pp.1856-1863
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• 2003

Overlay model had several advantages to describe hysteretic behavior of material and showed good capability for many engineering materials. However, this model is only applicable to material obeying Masing postulate. Some materials such as 316L stainless steel do not follow Masing postulate and show cyclic hardening(or softening) and strain range dependence. Low cycle fatigue tests of 316L stainless steel at 600$^{\circ}C$ were performed to investigate the characteristics of cyclic behavior of non-Masing material. From all tests cyclic softening was observed. There were differences in elastic limit of hysteresis loop according to applied strain range. To consider these features, modified overlay model was developed. Yield stresses of subelements were divided into isotropic and anisotropic part to describe the non-Masing behavior. The plastic strain range memorization was introduced to consider the strain range dependence. The prediction using modified overlay model showed a good accordance to actual hysteresis loops.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.27 no.5
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• pp.482-487
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• 2005

Amelobalstic fibroma is a rare true mixed tumor of odontogenic origin with both mesenchymal and ectodermal components. It usually appears in the mandible and in the posterior segments of young patients without gender predilection, and sometimes is associated with an impacted tooth. It is a benign slow growing tumor that is less infiltrative than an ameloblastoma but tends to expand bone. Surgical treatment with excision followed by curettage seems to be the most appropriate therapeutic option. The objective of this presentation is to report a case of ameloblastic fibroma of the mandible body in a 14-year-old woman, to make a brief review of the literature about its differential diagnosis and its clinical and histologic features and the treatment.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.1
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• pp.65-70
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• 2012

Polymorphous low-grade adenocarcinoma (PLGA) is a neoplasm that is regarded as the second most common malignant salivary gland tumor after mucoepidermoid carcinoma. After the diagnosis of PLGA it is important to make a treatment decision and consider the prognosis. A histopathologic examination is necessary for diagnosis. Treatment is primarily surgical excision and long-term follow up is essential to evaluate local recurrences. This report describes 2 cases of PLGA located in the soft palate without any evidence of metastasis. The first case was PLGA with bony infiltration and an irregular margin lesion. The second case was PLGA localized in palatal soft tissue. We present diagnoses, histopathologic features, treatments and prognosis of PLGA.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.2
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• pp.194-197
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• 2008

Nasolabial cyst is a rare non-odonotogenic, soft-tissue, developmental cyst arising inferior to the nasoalar region of the face. The most common clinical finding of the nasolabial cyst is that of a slowly enlarging asymptomatic swelling typically without radiographic abnormalities. This case report describes a 25-year-old man in which the clinicopathologic findings and an erosive finding on the computed tomographic scan on maxilla were consistent with nasolabial cyst. The histopathologic features, differential diagnosis, treatment and prognosis are discussed.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.37
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• pp.5.1-5.4
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• 2015

Dry eye syndrome is a relatively common disease of the tears and ocular surfaces that results in discomfort, visual disturbance, and tear film instability with possible damage to the ocular surfaces. Microvascular submandibular gland (SMG) transfer offers a surgical alternative for a permanent autologous substitution of tears using the basal secretion of a transplanted SMG. Long-term follow-up reveals that this technique is a lasting and effective solution for patients with severe dry eye syndrome. The uncomfortable symptoms were relieved, and the frequency of use of pharmaceutical tear substitutes was reduced. Objective examination showed significant improvement in tear film and some features of ocular surface such as breakup time of tear film and corneal staining. Patients may suffer from obstruction of Wharton's duct or epiphora after surgery. Activation of secretion-related receptors could improve the early hypofunction of the denervated SMG and prevent the duct obstruction. Reduction surgery, partial SMG transplantation, uses of atropine gel or Botulinum toxin A could be the choices of treatment for epiphora.

• Steel and Composite Structures
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• v.16 no.3
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• pp.253-267
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• 2014

Based on the test on a 1/2.5-scaled model of a two-bay and three-story inner frame composed of reinforced concrete beams and lattice steel reinforced concrete (SRC) irregular section columns under low cyclic reversed loading, the failure process and the features of the frame were observed. The subsequence of plastic hinges of the structure, the load-displacement hysteresis loops and the skeleton curve, load bearing capacity, inter-story drift ratio, ductility, energy dissipation and stiffness degradation were analyzed. The results show that the lattice SRC inner frame is a typical strong column-weak beam structure. The hysteresis loops are spindle-shaped, and the stiffness degradation is insignificant. The elastic-plastic inter-story deformation capacity is high. Compared with the reinforced concrete frame with irregular section columns, the ductility and energy dissipation of the structure are better. The conclusions can be referred to for seismic design of this new kind of structure.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.2
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• pp.117-126
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• 2012

Epidermolysis bullosa (EB) represents a spectrum of conditions that are characterized by blistering and mechanical fragility of the skin. There is genetic heterogeneity and marked variation in clinical phenotypes in the multiple EB disorders. The most recent classification recognizes four major EB grouping and over 30 EB subtypes. The severity of EB ranges from mild to severe skin involvement, and it can be localized or generalized. Oral features include repeated occurrence of blisters, erosions, and scars, which lead to limited mouth opening, ankyloglossia, elimination of buccal vestibule, and increased risk of oral carcinoma. Routine dental care or even normal tooth brushing might cause bullae on the oral mucosa. Occasionally, the clinician will be called upon to treat patients with EB and should therefore be aware of specific treatment modifications. we present a reviews of the literature with a case providing adequate anesthetic and surgical care.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.14 no.3
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• pp.228-236
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• 1992

This study was to designed to evaluate the reactions of mouse femoral bone to bone wax. In sixteen mice with a strain of I. C. R. mouse weighed approximately 300 to 850g 2.0~2.0mm sized bone defects were created by drilling. Half of mice were inserted by bone wax and the remainder serving as control without bone wax application. The mice were sacrificed 1, 2, 6, 8 weeks after operation and block specimens were prepared for light microscopy examination. The results obtained were as follows. 1. Histologic features of tissue reaction to bone wax were the presence of inflammatory cell infiltration and multinucleated giant cell. 2. Bone ear healing from the created margin were markedly impaired by the application of bone wax 3. New bone formation was markedly decreased in bone wax application.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.1
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• pp.100-103
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• 1991

In the treatment of mandibular prognathism with concomitant features of narrow alar base and some paranasal deficiency, simultaneous paranasal augmentation for the additional esthetic effect can be considered, if it is determined to correct the mandibular prominence and class III by a mandibular set-back. Alloplastic augmentation has several advantages upon the autogenous means in the respect of dimensional stability and simplicity of operation. This is a case report of silastic paranasal augmentation performed simultaneously with mandibular set-back surgery which has a period of 15 months of follow-up postoperatively.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.16 no.2
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• pp.196-201
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• 1994

One case of an unusual form of carcinoma involving the submucosal gland and duct of tongue was reported and reviewed. According to Gerughty et al(1968) four distinct component parts were classified : ductal carcinoma in situ(involvement of the ductal epithelium by in situ carcinomatous changes), squamous cell carcinoma, and a mixed carcinoma(combination of glandular and squamous characteristics and occasionally consisted of large nests composed of "glassy" cell). This tumor was fond to be extremely aggressive and highly malignant. The histopathologic features and the clinical behavior of this tumor were sufficiently distinctive to warrant the designation adenosquamous carcinoma : exhibit concomitant glandular and squamous neoplasm. The mode of therapy was evaluated and the treatment of choice appears to be radical surgery. So, we has done the radical neck dissection and partial glossectomy. However, the limited number of cases indicated that collection and subsequent analysis of additional cases must be performed before any definitive conclusion can be drawn.