• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.6
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• pp.121-126
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• 2006

Snap-fit is being used in manufacture of plastic products. Integral features using snap-fit are classified as locks, locators and enhancements. Locking features complete the process of attachment by providing physical interference to prevent separation. Looking feature pairs consist of two components, i.e., a flexible latch and a rigid catch and require particular care and attention for their selection. We can make several locking feature pairs by selecting latch and catch, but some parts restrict freedom of selection. Therefore, part designers must know the characteristic properties of generic locking feature forms as considering a specific design problem. In this paper, it has been presented about problem of small size products using locking feature and then introduced new locking feature applicable to small parts.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.1394-1397
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• 1993

A Fuzzy Microprocessor(FMP) is presented, which is suitable for real-time control applications. The features include high speed inference of maximum 114K FLIPS at 20MHz system clocks, capability of up to 128-rule construction, and handing of 8 input variables with 8-bit resolution. In order to realize these features, the fuzzifier circuit and the processing element(PE) are well optimized for LSI implementation. The chip fabricated in 1.2$\mu\textrm{m}$ CMOS technology contains 71K transistors in 82.8 $\textrm{mm}^2$ die size and is packaged in 100-pin plastic QFP.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.263-267
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• 2002

We are standing at the beginning of the industrialization of flexible thin-film transistor backplanes. An important group of candidates is based on silicon thin films made on metal or plastic foils. The main features of amorphous, nanocrystalline and microcrystalline silicon films for TFTs are summarized, and their compatibility with foil substrate materials is discussed.

• Archives of Plastic Surgery
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• v.36 no.3
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• pp.356-360
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• 2009

Purpose: Lipofibromatous Hamartoma(LFH) of nerve is a tumor - like lipomatous process principally involving the young persons. This is rare disease characterized by a soft slowly growing mass surrounding and infiltrating major nerves and their branches of the palm and digits. LFH of nerve usually affects the median nerve, with the most common sites of presentation being the distal forearm and hand in the wrist or palm. It may cause symptoms of compression neuropathy and is associated with macrodactyly. Recently, MRI plays a major role in confirming the diagnosis of LFH. Therefore, we present two cases of LFH in the hand with MRI features and surgical management. Methods: One is 6 - years - old female who presented with macrodactyly involving both the soft tissue and bony parts of the second, third and forth digits of her right hand. The other one is 16 - years - old man who presented involving the soft tissue of the second and third digits of his right hand, with pain and numbness, along with motor and sensory deficits in the median nerve distribution. To evaluation about LFH, we enforced preoperative MRI and physical examination. After confirming the diagnosis of LFH, we proposed decompression of all compromised peripheral nerve to help alleviate pain and paresthesia to reduce the likelihood of permanent motor and sensory sequelae. Results: A characteristic feature on MRI is the appearance of serpentiform nerve fascicle surrounded by fibro - fatty tissue within the expended nerve sheet. Distribution of fat between fascicles is asymmetric. Two cases were treated by limited debulking of the redundant tumor tissue and excision of epineurial fatty tissue. These cases were performed with relief of symptom. Conclusion: MRI not only confirms the diagnosis, it also provides a detailed assessment of nerve involvement preoperatively. Especially, on coronal images, the nerve has a spagetti - like appearance that is pathognomonic of LFH. Recommendations for early treatment include decompression of the carpal tunnel, debulking of the fibro - fatty sheath, microsurgical dissection of the neural elements and excision of involve nerve with or without grafting.

• Archives of Reconstructive Microsurgery
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• v.16 no.1
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• pp.48-51
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• 2007

There could be several methods for trochanteric reconstruction including local flap, pedicled perforator flaps, free flap, etc. We performed greater trochanteric reconstruction with lumbar artery perforator free flap in some aberrant method. So we report this experience with review of literatures. A 42-year-old man visited our hospital with a large soft tissue defect in his left greater trochanteric area by traffic accident. The patient had wide skin and soft tissue defect combined with open femur fracture. During one month period of admission, he underwent femur open reduction and wound debridement four times. After that we planned thoracodorsal perforator free flap reconstruction. The flap was outlined as large as $20{\times}15\;cm$ and elevated in a suprafascial plane from the lateral border. During intramuscular perforator dissection, we found that two 1.5 mm diametered perforator vessels coursed inferomedially toward second lumbar region. Finally the flap became lumbar artery perforator flap based on second lumbar artery perforator as a main pedicle. After flap transfer, the perforator vessels were connected with inferior gluteal artery and vein microsurgically. The operation was successful without uneventful course. We found no significant postoperative complication and donor site morbidity during six months follow up periods. Lumbar artery perforator flap could be an alternative procedure for thoracodorsal perforator flap in some patients with anatomic variant features.

• Archives of Craniofacial Surgery
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• v.17 no.3
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• pp.173-175
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• 2016

Chondroid syringoma is a rare mixed tumor of the skin which is composed of both mesenchymal and epithelial cells. Its incidence at less than 0.1% and is frequently located on the head and neck. Chondroid syringoma is easily confused with epidermal cysts. Since malignant forms of chondroid syringoma have been reported, accurate and timely diagnosis is important for proper management. We report clinical and histological features of chondroid syringoma in 5 patients treated at our institution. In most of the cases, chondroid syringoma presented as a round, firm, nodular or cystic lesion that had well marginated heterogeneity in sonography. Clinically, all of the lesions were removed by simple excision. Microscopically, all five tumors were well circumscribed and consisted of epithelial, myoepithelial, and stromal components. The epithelial component formed tubules lined by one or more rows of eosinophilic epithelial cells. The outer layer of tubules appeared to be flattened myoepithelial cells. The stroma is myxoid and contained spindle shaped myoepithelial cells. We expect that the clinical, sonographic, and histological data from our report may help clinicians who are confronted with various kinds of analogous facial lesions to decide the most proper management for their patients.

• Archives of Craniofacial Surgery
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• v.9 no.1
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• pp.31-34
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• 2008

Introduction: Lymphoepithelioma-like carcinoma of the skin (LELCS) is a rare cutaneous tumor of low grade malignancy and microscopically resembles lymphoepitheliomatous malignancies in the nasopharynx, palatine tonsils, salivary glands and uterine cervix. LELCS presents as scarlet-colored firm nodules or plaques on the face, scalp, or shoulder of middle-aged to elderly individuals. Material and Methods: A 72 year-old female had complained a papule like lesion with intermittent pruritis on the left temple for 2 years. But the lesion was changed to scarlet-colored firm nodule with ulceration. The mass was diagnosed as LELCS on the biopsy. And to confirm that the mass is not metastatic lymphoepithelioma-like carcinoma from other sites or direct tumor extension from the nasopharynx, selective radiographic and laboratory tests were done carefully. Results: Wide excision was performed with general endotracheal anesthesia. The tumor is composed of island of large epithelial cells surrounded by as dense infiltrate of lymphocytes. Immunohistochemical staining with cytokeratin and epithelial membrane antigen(EMA), the tumor cells were positive reaction for stain. And Epstein-Barr virus genome was not detected by in situ hybridization. So, the tumor was confirmed as LELCS. Conclusion: LELCS was described by Swanson at 1988, but has not been reported in the field of plastic surgery of Korea. We report a case of primary LELCS that occurred in the left temple with clinical characteristics, histologic features and references.

• Archives of Plastic Surgery
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• v.35 no.6
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• pp.723-728
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• 2008

Purpose: The disinsertion of the phalangeal tendon distal insertion has difficulties in ordinary tenorrhaphy operation for the anatomical features, and still has controversy between non-surgical and surgical management. The purpose of this study is to select treatment for the injury of the phalangeal tendon distal insertion, as we've had a good results from operation treatment with Pull-in suture technique. Methods: We reviewed the hospital records of 12 patients treated with Pull-in suture technique with disinsertion of the phalangeal extensor or flexor tendon distal insertion from June 2006 to June 2007. Eight patients were involved with the tendon disinsertion without bone fracture, and 4 patients were involved with the fracture of the phalangeal tendon distal insertion site. After removal of the K-wire in week 6, active physical exercises were commenced immediately. The mean follow-up period was 12.4 months. Results: All the patients who had tendon disinsertion with bone fracture had IIB, by Wehbe and Schneider's classification 2, and we evaluated the results comparing the same finger of the other hand according to Crawford's evaluation criteria 5. The nine excellent and three good results were obtained and there were no limitation of motor for the patient who had operation for the rupture of flexor tendon as well. There were no particular complications during the follow-up period. Conclusion: The most important thing for the disinsertion of the phalangeal tendon distal insertion is to maintain an accurate and durable reduction state keeping the tension of tendon. At this point, after removal of the K-wire, the Pull-in suture technique allows accurate realignment of the tendon-bone unit without any specific instrumentation under the more stable state. The Pull-in suture technique seems to be a strong alternative for the treatment of disinsertion of the phalangeal tendon distal insertion, with successful treatment outcome(rapid functional recovery and high patient satisfaction).

• Tunnel and Underground Space
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• v.8 no.3
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• pp.234-248
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• 1998

This paper presents a new constitutive model for numerical modeling the shear behaviour of rough rock joints. The model incorporates the dilatancy of joints on the basis of elasto-plastic theory. Barton's empirical shear strength formular are adopted in the formulation process. The mobilized JRC concept is evoked to address the shear strength hardening and sofrening phenomena. The mobilized JRC in the pre- and post-peak range is approximated by assuming that the variation of JRC is a function of tangential plastic work. Discrete finite joint element is used to implement the proposed constitutive model. The model is validated by the numerical direct shear test on a single joint which is subjected to different boundary conditions. The test results are in good agreement with the experimental observations reported by other authors. The numerical tests also exhibit that the proposed model can simulate the salient features envisaged in the behaviour of rough rock joints.

• Archives of Craniofacial Surgery
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• v.19 no.1
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• pp.3-12
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• 2018

Background: Millard's rotation-advancement repair, which is used by many surgeons, can make a natural philtral column, but most surgeons use a modification of the rotation-advancement flap. The purpose of this article is to introduce a modification utilized by the authors and to provide detailed surgical procedure. Methods: We retrospectively reviewed 82 patients' medical records and presented surgical technique and outcomes. The main features of the authors' strategy are emphasizing horizontal length of the lip, orbicularis oris muscle duplication for improving the definition of the philtral column, overcorrection of domal portion than the non-cleft side in order to compensate for the recurrence during growth. Two judges rated two times the appearance of the patients' nose and lip using Asher-McDade aesthetic index. Intra- and interobserver reliabilities were determined using Cohen's kappa statistics. Results: All patients recovered eventually after surgery; however, two patients have a minor complications (wound infection in one patient, wound disruption due to trauma in the other patient). The improvement of the aesthetic results can be achieved with this modified Millard technique. Total mean scores of the Asher-McDade index was 2.08, fair to good appearance. The intraobserver reliabilities were substantial to almost perfect agreement and the interobserver reliabilities were moderate to almost perfect agreement. Conclusion: We modified Millard method for repair of complete unilateral cleft lip. The surgical outcomes were favorable in long-term follow-up. We hope our technique will serve as a guide for those new to the procedure.