• Journal of Surface Science and Engineering
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• v.39 no.3
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• pp.98-104
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• 2006

Al-doped ZnO (AZO) films were deposited on the plastic substrate by inductively coupled plasma (ICP) assisted DC magnetron sputtering. The AZO films were produced by sputtering a metallic target (Zn/Al) in a mixture of argon and oxygen gases. AZO films with an electrical resistivity of ${\sim}10^3\;{\Omega}cm$ and an optical transmittance of 80% were obtained even at a low deposition temperature. In-situ process control methods were used to obtain stable deposition conditions in the transition region without any hysteresis effect. The target voltage was controlled either at a constant DC power. It was found that the ratio of the zinc to oxygen emission intensity, I (O 777)/I (Zn 481) decreased with increasing the target voltage in the transition region. The $Ar/O_2$ plasma treatment improve the adhesion strength between the polycarbonate substrate and AZO films.

• Tribology and Lubricants
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• v.37 no.2
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• pp.54-61
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• 2021

The effect of the sand blasting before TiAlN coating in the manufacture of WC hard metal alloy tips have been studied. For four different tips, according to the status of processing of the sand blasting and the coating, residual stress measurement by X-ray diffraction and several tests for mechanical properties have been conducted. The results suggest that there was no difference in static mechanical properties, such as hardness, surface roughness and elastic modulus, between two coatings. Furthermore, compressive residual stress was generated equally on their surfaces. Additionally, the compressive residual stress in substrate WC was found to increase greatly when subjected to sand blasting treatment. However, the compressive residual stress decrease after coating regardless of sand blasting treatment. Nevertheless, it is confirmed that the compressive residual stress generated in the coating after sand blasting is less than that in the non-sandblasting coating. This was attributed to the plastic deformation occurring in the WC substrate during coating after sand blasting. In contrast to the scratch test results, sand blasting was assumed to have a negative effect on the adhesion between the coating and substrate. This is because there is a high possibility of microcracks due to plastic deformation in the WC substrate under the coating after sand blasting.

• Journal of Powder Materials
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• v.27 no.2
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• pp.111-118
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• 2020

The convergence of artificial intelligence with smart factories or smart mechanical systems has been actively studied to maximize the efficiency and safety. Despite the high improvement of artificial neural networks, their application in the manufacturing industry has been difficult due to limitations in obtaining meaningful data from factories or mechanical systems. Accordingly, there have been active studies on manufacturing components with sensor integration allowing them to generate important data from themselves. Additive manufacturing enables the fabrication of a net shaped product with various materials including plastic, metal, or ceramic parts. With the principle of layer-by-layer adhesion of material, there has been active research to utilize this multi-step manufacturing process, such as changing the material at a certain step of adhesion or adding sensor components in the middle of the additive manufacturing process. Particularly for smart parts manufacturing, researchers have attempted to embed sensors or integrated circuit boards within a three-dimensional component during the additive manufacturing process. While most of the sensor embedding additive manufacturing was based on polymer material, there have also been studies on sensor integration within metal or ceramic materials. This study reviews the additive manufacturing technology for sensor integration into plastic, ceramic, and metal materials.

• Journal of the Korean Vacuum Society
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• v.13 no.4
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• pp.175-181
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• 2004

We investigated the stability of the DLC film coated on 304 stainless steel substrate by Radio frequency assisted chemical vapor deposition method. Fracture and spallation behaviour of the coating was observed during micro-tensile test of the fil $m_strate composite. As the tensile deformation progressed, the cracks of the film were observed in the perpendicular direction to the tensile axis. Further deformation resulted in the plastic deformation with $45^{\circ}$ slip bands on the substrate surface. Spallation of the film occurred with the plastic deformation, which was initiated at the cracks of the film and was aligned along the slip directions. We found that both the cracking and the spallation behaviors are strongly dependent on the pre-treatment condition, such as Ar plasma pre-treatment. The spallation of the film was considerably suppressed in an optimized condition of the substrate cleaning by Ar glow discharge. We observed the improved stability with increasing duration of Ar plasma pre-treatment.nt.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.5
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• pp.396-403
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• 2006

Changes in cell adhesion molecules are associated with infiltration and metastatic progression of cancer. Reduced expression of E-cadherin and ${\beta}-catenin$ complex in some carcinomas has been reported. The changes in the expression in oral squamous cell carcinoma (OSCC) is not fully understood and it also remains undetermined whether the expression of these adhesion molecules in metastatic lesions differs from that in the primary lesions. In the present study, therefore, we immunohistochemically examined the expression of E-cadherin and ${\beta}-catenin$ in 45 primary OSCCs and 19 metastatic lymph nodes. We compared the expression of these molecules between primary and metastatic lesions and investigated the correlation between the expression and clinicopathologic parameters. The expression of E-cadherin and ${\beta}-catenin$ was reduced in 35/45 (78.2%), 14/45 (31.2%) of primary tumors respectively, but 18/19 (94.7%) and 17/19 (89.4%) of lymph nodes showed preserved expression. The reduced expression of the E-cadherin was associated with lymph node metastasis, invasive mode and marginal status but no significant relationship was not found with ${\beta}-catenin$. In conclusion, the loss of E-cadherin and ${\beta}-catenin$ complex function is associated with progression of OSCC and suggest that the expression of this complex will be a supplementary prognostic tool.

• Journal of Adhesion and Interface
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• v.3 no.4
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• pp.1-9
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• 2002

The main goal of this study was to analyze the effect of process additives, i.e. maleated polypropylene (MAPP), and nucleating agent on the viscoelastic properties of different types of extruded polypropylene-wood plastic composites manufactured from either PP homopolymer, high crystallinity PP or PP impact copolymer using dynamic mechanical thermal analysis. And also, the esterification reaction between wood flour and maleated polypropylene, and its role in determining the mechanical properties of wood flour-polypropylene composites was investigated. The wood plastic composites were manufactured using 60% pine wood flour and 40% polypropylene on a Davis-Standard $Woodtruder^{TM}$. Dynamic mechanical thermal properties, polymer damping peaks(than ${\delta}$), storage modulus (E') and loss modulus (E") were measured using a dynamic mechanical thermal analyzer. XPS (X-ray Photoelectron Spectroscopy), also known as ESCA (Electron Spectroscopy for Chemical Analysis) study of wood flour treated with MAPP was performed to obtain information on the chemical nature of wood fiber before and after treatment. To analyze the effect of frequency on the dynamic mechanical properties of the various composites, DMA tests were performed over a temperature range of -20 to $100^{\circ}C$, at four different frequencies (1, 5, 10 and 25 Hz), and at a heating rate of $5^{\circ}C/min$. From these results, the activation energy of the various composite was measured using an Arrhenius relationship to investigate the effect of maleated PP and nucleating agent on the measurement of the interphase between the wood and plastic of the extruded polypropylene wood plastic composites.

• Archives of Plastic Surgery
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• v.38 no.1
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• pp.81-84
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• 2011

Purpose: Nerve injury is one of the complication which can develop after brow lift. Peripheral nerve ending which is stretched from supraorbital nerve and supratrochlear nerve can be injured and symptoms such as pain, dysesthesia may appear. Usually, developed pain disappeared spontaneously and does not go on chronic way. We experienced a case that a patient complained chronic pain after brow lift which was not controlled by conservative management such as medications, local nerve block and report a successful surgical treatment of chronic pain after brow lift. Methods: A 24-year-old male who received brow lift with hairline incision at local hospital was admitted for chronic pain at the right forehead. The pain was continued for 3 months even though fixed thread was removed. Local nerve block at trigger point with mixed 1 mL 2% lidocaine and 1 mL Triamcinolone acetonide was done and oral medications, Gabapentine and carbamazepine, were also applied but there was no difference in the degree of pain. Therefore the operation was performed so that careful dissection was carried out at right supraorbital neurovascular bundle and adhered supraorbital nerve was released from surrounding tissues and covered with silastic sheet to prevent adhesion. Results: The pain was gradually relieved for a week. The patient was discharged without complications. No evidence of recurrence has been observed for 2 years. Conclusion: The pain developed after brow lift was engaged with nerve injury and sometimes remains chronically. Many kinds of conservative management to treat this complication such as medications, local nerve block have been reported and usually been used. But there are some chronic cases that conservative treatment do not work. In sum, we report 1 case of successful surgical treatment for relief of intractable pain developed after brow lift surgery.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.1
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• pp.65-69
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• 2008

This work shows that the grinding-induced scratches formed on the back surface of silicon chips can highly influence the flexural strength of the chips. Meanwhile, in a case that excellent adhesion between the back surface and the plastic package body maintains, the flexural strength of plastic-encapsulated packages is not so sensitive to the geometry of the scratch marks. This article explains why such different flexural fracture behavior between bare chips and plastic-encapsulated chips appears.

• Korean Journal of Head & Neck Oncology
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• v.3 no.1
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• pp.37-54
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• 1987

The aim of surgery for all parotid masses is directed toward total removal of the tumor with adequate safe margins of adjacent normal tissue and preservation of the facial nerve whenever possible. Reconstructive procedures following parotidectomy for benign or low grade malignant lesions are most commonly necessary if soft tissue deficits appear at the angle of the mandible below the earlobe as a major cosmetic deformity. This is a report of Z4 cases with a diagnosis of parotid tumor who were treated using various surgical procedures at Department of Plastic and Reconstructive Surgery, Hanyang University Hospital over the period of 4 years from January, 1983 to December, 1986. Among 24 cases, 11 cases were reconstructed by Sternocleidomastoid muscle flap at the same time that extirpative surgery is outlined. The advantage of Sternocleidomastoid muscle flap is the coverage of the facial nerve, so adhesion between the facial nerve and skin was prevented. Absorption and loss of bulk was not found such as dermofat graft. It was a simple method. Neither donor site defect nor sternocleidomastoid muscle deformity was developed. Sternocleidomastoid muscle flap have been found satisfactory in maintaining filled-out soft tissue hollows with good result cosmetically and functionally.

• Archives of Craniofacial Surgery
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• v.23 no.5
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• pp.228-231
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• 2022

Fibrin glue is a topical agent widely used for hemostasis, wound healing, and surgical adhesion. Complications of fibrin glue itself are extremely rare because it is absorbed over time, but can occur as a result of inappropriate application. We report a case of a postoperative complication caused by inappropriate application of fibrin glue in blow-out fracture surgery. A 65-year-old male patient presented with periorbital swelling and an open wound on the right infraorbital area. Computed tomography showed a right orbital floor fracture. After reduction of the herniated tissue into the orbit, an implant was inserted and fibrin glue was applied to stabilize the implant. This procedure was performed without difficulty, but the patient complained of persistent diplopia and limited eyeball movement after surgery. An imaging study showed a mass-like lesion, which was not a hematoma, in the orbital cavity. In a second operation, the mass was identified as clotted fibrin glue that had not been applied properly. After removal, the patient's symptoms were relieved without further complications. Appropriate and careful application of fibrin glue is necessary to avoid unnecessary complications.