• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.799-802
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• 2008

The metal films ink-jetted using the conductive ink based on a mixture of copper and silver nanoparticles were investigated. The porosity and resistivity of films were minimized by adjusting the mixing ratio of Cu and Ag nanoparticles. We demonstrated that the printed tracks with good conductivity could be obtained at sufficiently lower annealing temperatures where plastic substrates could be used.

• Bulletin of the Korean Chemical Society
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• v.20 no.8
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• pp.885-892
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• 1999

This communication describes the synthesis of : (i) non-toxic and low cost nanocrystalline electrode materials, which can be prepared advantageously at low temperature ; (ii) highly conductive electrolyte membranes formed by the nano-encapsulation within a poly(acrylonitrile)-based polymer matrix of a solution of LiPF6 in organic solvants. The performances of rechargeable PLR (Plastic Lithium Rechargeable) batteries using the above mentioned components are presented.

• Journal of Information Display
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• v.1 no.1
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• pp.14-19
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• 2000

Due to distinct properties of plastic substrates such as poor thermal resistance, non-rigidness and high thermal expansion, it is difficult to fabricate plastic film LCDs by conventional LCD processes. Poor thermal resistance and high thermal expansion of substrates induced deformation of substrates surface, mismatch of thermal expansion between ITO electrodes and substrates resulted in defects in the ITO electrodes during the high temperature process. Defects of ITO electrodes and non-uniform cell gap caused by non-rigid and flexible properties were also observed in the pressuring process. Based on in these observations, we used a newly developed material and fabrication process to prevent deformation of substrates, defects of electrodes and to maintain uniform cell gap. The maximum temperature of the process is limited up to $110^{\circ}C$ and pressure loaded during the process is five times less than conventional one. With these invented processes and materials, we obtained highly reliable Plastic Film STN LCDs whose electro-optical characteristics are better than or equivalent to those of typical glass LCDs.

• Archives of Plastic Surgery
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• v.36 no.3
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• pp.344-347
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• 2009

Purpose: Malignant soft tissue tumors, known as sarcomas, are well known to be locally aggressive, frequently metastatic, and highly recurrent. In other hands, intermediate soft tissue tumors often recur locally with adjacent tissue infiltration so the clinical management is difficult as sarcoma. In the present study, we evaluate the clinical course of the intermediate soft tissue tumors and consider the management plan for those. Methods: From March, 1998 to April 2008, total 3 patients of intermediate soft tissue tumors underwent operations. A patient with fibrohistiocytic neoplasm, a free flap reconstruction was performed, and he underwent several more operations because of recurrences. Other patients with desmoids - type fibromatosis showed local invasion and adhesion, and one of them underwent reoperation due to local recurrence. Results: 2 of 3 patients underwent recurrences of tumors and reoperations were performed. In another patient with no recurrence, follow-up period was just 5 months, so there may be recurrence of tumor in long term follow-up. Conclusion: The clinical course of intermediate soft tissue tumors shows high recurrence rate. So clinically, intermediate soft tissue tumors should be considered as sarcomas. The successful management requires wide resection, carefully planned reconstruction, and close follow up with radiologic evaluation.

• Archives of Plastic Surgery
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• v.32 no.3
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• pp.271-280
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• 2005

There are various types of flap in head and neck reconstruction. We chose the appropriate flap considering the indication and patient's condition. In case of conventional flaps, its type is decided according to the reconstruction site. In other words, the types of considerable flaps are limited in a way. But, perforator flaps can reduce donor limitation and harvest flaps depending on the condition of the recipient. Therefore, the flap is very useful for the head and neck reconstruction needed for 2-dimensional or 3-dimensional reconstruction. We report the 29 cases of perforator-based flap including 8 cases of latissimus dorsi perforator free flap, 5 thoracodorsal perforator free flap, 4 anterolateral thigh perforator free flap, 3 peroneal osteocutaneous perforator free flap and 9 submental perforator island flap for the head and neck reconstruction. Free flaps include 2 cases of chimeric pattern, 7 controlled resurfacing pattern, 4 3-D pattern, 3 dermoadiposal pattern, 1 folded pattern and 3 osteocutaneous pattern. The flaps were successfully used for the head and neck reconstruction. But one patient died during a follow up period because of the recurrence of tumor. Various perforator flaps(island/free pattern) can be highly competitive to the conventional flaps in the head and neck reconstruction, considering a thin character for resurfacing, more flexible and versatile option, variable composition, long pedicle with donor structures saved, and less prominent donor morbidity.

• Proceedings of the KWS Conference
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• 2004.05a
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• pp.316-318
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• 2004

In recent years, plastic waste has been recognized as a worldwide environmental issue. To solve the disposal problem of the plastic waste, alternative treatment such as the use of biodegradable plastic(polybutylene succinate: PBS) is indeed highly in demand due to its merit of PBS buried in soil decomposed into carbon dioxide and water. In the present study, for the production of further functional PBS with TiO$_2$ as photocatalyst, which shows the decomposition of detrimental organic compound and pollutant under ultraviolet irradiation, we attempted to prepare photocatalytic TiO$_2$ coatings on PBS substrate by HVOF and plasma spraying techniques under various conditions using three kinds of agglomerated powders (P200: 200nm, P30: 30nm, P7: 7nm). The microstructures of coatings were characterized with SEM and XRD analysis, and the photocatalytic efficiency of coatings was evaluated through the photo degradation of gaseous acetaldehyde. Therefore, such functional TiO$_2$-Plastic composite material is expected to considerably contribute to the reduction of aggravated environmental problem.

• Archives of Plastic Surgery
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• v.32 no.1
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• pp.37-42
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• 2005

The human nose is located in the center of the face and it's cosmetic importance is high. The contour of the nasal dorsum and side walls play a major role in the shaping of the nose, and even a slight distortion may results in significant variance of the human facies. However, in the case of patients with wide nasal bone, augmention rhinoplasty can make nasal planes look wide, resulting in bulbous appearing noses or lateral borders of the nasal implant may be visible after the surgery making the final cosmetic results unsatisfactory. To solve such problems, from march, 1999 to march, 2004, the authors have performed augmention rhinoplasty in 36 patients. The cause of operations were as follows: flat nose 20, hump nose 5, deviated nose 4, secondary rhinoplasty 7. Paramedian osteotomy was performed at a distance that was the same as the width of the implant from the midline(5 mm + 5 mm). To prevent it from connecting to the roof at the lateral osteotomy line, intentional green stick fracture of the roof was performed. Agumentation rhinoplasty was done with either Silicone or Gortex and ear cartilage as a supplement. The follow up period was 2 weeks to 13 months with an average of 5.5 months. There were no infections and postoperative bleeding. As a result, the nose was augmented higher and narrower than before which we and the patient both found highly satisfactory.

• Archives of Plastic Surgery
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• v.32 no.1
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• pp.105-109
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• 2005

Perineal area is composed of compact structures of urogenital organs and anus requiring a more sophisticated selection of flap and reconstruction. For achieving better outcome then conventional flap surgery, we use the perineal perforator based island flap for its reconstruction. After locating the perforator by Doppler, the flaps were designed according to the defect or expected vaginal orifice. The flaps were elevated bilaterally as island pattern. Finally defect or neovagina was reconstructed with inconspicious linear scar hidden in the inguinal crease. Five cases were performed with the perineal perforator based island flap. There were 3 cases of vulvar cancer, 1 case of transsexualism, and 1 case of ambiguous genitalia because of congenital adrenal hyperplasia. Operative results were satisfactory with good contouring and less prominent donor scar, when they were compared with other flap reconstructions such as latissimus dorsi perforator flap, groin flap, gracilis myocutaneous flap etc. The perineal perforator based island flap is highly recommended with the advantages of easy flap elevation, good rotation arc, and appropriate flap thickness for contouring. Compared with other conventional flaps, it can be selected as a good option for moderate defect of perineal area.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.14 no.1
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• pp.10-15
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• 2003

Background and Objectives : Ankyloglossia, commonly known as tongue-tie, is the result of a short, fibrous lingual frenulum or highly attached geioglossus muscle. This condition may cause sucking and swallowing problems, articulation disorders, interference with the tongue's cleansing action, increased the potential for caries, and inability to lick the lips, play a wind instrument, and 'french kiss' Treatment is surgical procedure. In the most cases, horizontal sectioning and mucosal suture(the conventional procedure) is preferred, but in some cases, the Z-plastic procedure is effective. This study is aimed to compare the result of the two procedures. Materials and Methods : Twenty tongue-tie patients underwent operation. Ten patients were treated with the Z-plastic procedure and ten patients were treated with the conventional method randomly. We checked preoperative mobile tongue length, postoperative mobile tongue length, operation time and postoperative wound states. Results : Among the 20 cases of tongue-tie, 2 cases are excepted due to pre-operative state, thus we compared 18 cases of tongue-tie patients. There is no statistically significant difference between the two procedures except in operation time. The Z-plastic procedure apparently needs a little more operating time. Conclusion : Patients treated with the Z-plastic procedures appeared to have better outcomes, but the data shows no statistical significance except in operating time. Consequently, the Z-plastic procedure is indicated in a limited amount of cases.

• Steel and Composite Structures
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• v.14 no.6
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• pp.571-586
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• 2013

This paper focuses on the buckling capacity of a hybrid grid shell. The eigenvalue buckling, geometrical non-linear elastic buckling and elasto-plastic buckling analyses of the hybrid structure were carried out. Then the influences of the shape and scale of imperfections on the elasto-plastic buckling loads were discussed. Also, the effects of different structural parameters, such as the rise-to-span ratio, beam section, area and pre-stress of cables and boundary conditions, on the failure load were investigated. Based on the comparison between elastic and elasto-plastic buckling loads, the effect of material non-linearity on the stability of the hybrid barrel vault is found significant. Furthermore, the stability of a hybrid barrel vault is sensitive to the anti-symmetrical distribution of loads. It is also shown that the structures are highly imperfection sensitive which can greatly reduce their failure loads. The results also show that the support conditions pose significant effect on the elasto-plastic buckling load of a perfect hybrid structure.