• Current Applied Physics
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• v.18 no.11
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• pp.1399-1402
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• 2018

Nanorod films of cobalt oxide ($Co_3O_4$) have been grown by a unique oblique angle deposition (OAD) technique in an e-beam evaporator for supercapacitor electrode applications. This technique offers a non-chemical route to achieve large aspect ratio nanorods. The fabricated electrodes at OAD $80^{\circ}$ exhibited a specific capacitance of 2875 F/g. The electrochemically active surface area was $1397cm^{-2}$, estimated from the non-Faradaic capacitive current region. Peak energy and power densities obtained for $Co_3O_4$ nanorods were 57.7 Wh/Kg and 9.5 kW/kg, respectively. The $Co_3O_4$ nanorod electrode showed a good endurance of 2000 charge-discharge cycles with 62% retention. The OAD approach for fabricating supercapacitor nanostructured electrodes can be exploited for the fabrication of a broad range of metal oxide materials.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.1
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• pp.175-180
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• 2008

Traumatic injuries to the primary dentition are commonly encountered problems in dental practice. It is found that 30% of the children had injuries to the primary dentition and 22% to the permanent dentition. The greatest incidence of trauma to the primary dentition occurs at the ages of 2 and 3 as children start to learn motor coordination. Because teeth and alveolar bone are traumatized simultaneously, alveolar bone fractures are likely to occur when multiple teeth are involved in injuries. Dental splints are indicated for the management of maxillofacial fractures. They enable anatomic reduction of fractured segments and help immobilization and maintenance of the fragments after reduction. They also act as a stabilizer during rehabilitation. Various types of dental splints are available. In this case, routine resin-wire splint technique could not be applied because of the child's uncooperative behavior. Oral sedation was not indicated because N.P.O. had not been preceded. Therefore, we decided to use open-cap acrylic splint instead. Stabilization using open cap acrylic splint requires minimum chair time with reduced discomfort to both patient and dentist. It is an effective means of splint for uncooperative children and especially useful when other means of fixation have been failed. Because trauma on the primary dentition can affect the underlying permanent tooth germ, it is important to monitor eruption process of the permanent dentition.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.21-26
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• 2014

When iodine container for dental mouth treatment is opened, thread for treatment is cut by the blade in cap of container. Due to the problem of corrosion in a short period time after the reaction of metal blade to iodine solution, it gives impact on patient hygiene. In order to solve the problem, alternative products such as ceramic blade are developed and produced recently. In case of ceramic blade, it is produced by handwork and machine work. In this study, for the quantity production of ceramic blade with powder injection molding, we proposed a delivery system to have uniform charge of 20 cavity. Using Moldflow, simulation on 20 Cavity flow was performed. And then the mold was obtained through mold production and modification.(based on simulation) After injection molding, debinder, sintering process was achieved for ceramic blade, and the cap product was completed via insert injection on ceramic blade. In this study, we verified possibility of quantity production of ceramic blade which showed effective performance for cutting.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.334-338
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• 2005

Method was developed to efficiently analyze semicarbazide (SEM) in foods. Although SEM is produced by thermal decomposition of blowing agent azodicarbonamide, it is too small to be activated by ultraviolet light or fluorescence. When 2-nitrobenzaldehyde semicarbazone, derivatization of SEM, was analyzed by HPLC with triple column system, coefficient correlation over 0.9997 and detection limit of 0.48 ng/g were observed. SEM level in commercial bottle cap gasket was 812.20-5771.30ng/g. Recoveries for SEM in food and PVC gasket were 83.45-97.33% and 92.12-98.71%, respectively. SEM level in plastic seals of press twist-off metal lids was ND-5771.330ng/g.

• Journal of Adhesion and Interface
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• v.24 no.2
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• pp.60-63
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• 2023

The AlGaN/GaN heterostructure has high electron mobility due to the two-dimensional electron gas (2-DEG) layer, and has the characteristic of high breakdown voltage at high temperature due to its wide bandgap, making it a promising candidate for high-power and high-frequency electronic devices. Despite these advantages, there are factors that affect the reliability of various device properties such as current collapse. To address this issue, this paper used metal-organic chemical vapor deposition to continuously deposit AlGaN/GaN heterostructure and SiN passivation layer. Material and electrical properties of GaN HEMTs with/without SiN cap layer were analyzed, and based on the results, low-frequency noise characteristics of GaN HEMTs were measured to analyze the conduction mechanism model and the cause of defects within the channel.

• Membrane and Water Treatment
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• v.11 no.1
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• pp.11-23
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• 2020

The effectiveness of in situ sediment capping as a technique for heavy metal risk mitigation in Hyeongsan River estuary, South Korea was studied. Sites in the estuary were found previously to show moderate to high levels of contamination of mercury, methylmercury and other heavy metals. A 400 m × 50 m section of the river was selected for a thin layer capping demonstration, where the total area was divided into 4 sections capped with different combinations of capping materials (zeolite, AC/zeolite, AC/sand, zeolite/sand). Pore water concentrations in the different sites were studied using diffusive gradient in thin film (DGT) probes. All capping amendments showed reduction in the pore water concentration of the different heavy metals with top 5 cm showing %reduction greater than 90% for some heavy metals. The relative maxima for the different metals were found to be translated to lower depths with addition of the caps. For two-layered cap with AC, order of placement should be considered since AC can easily be displaced due to its relatively low density. Investigation of methylmercury (MeHg) in the site showed that MeHg and %MeHg in pore water corresponds well with maxima for sulfide, Fe and Mn suggesting mercury methylation as probably coupled with sulfate, Fe and Mn reduction in sediments. Our results showed that thin-layer capping of active sorbents AC and zeolite, in combination with passive sand caps, are potential remediation strategy for sediments contaminated with heavy metals.

• Current Applied Physics
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• v.18 no.11
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• pp.1458-1464
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• 2018

An improved method for the preparation of g-$C_3N_4$ is described. Currently, heating (> $400^{\circ}C$) of urea is the common method used for preparing the g-$C_3N_4$. We have found that sonication of melamine in $HNO_3$ solution, followed by washing with anhydrous ethanol, not only reduce the crystallite size of g-$C_3N_4$ but also facilitate intriguing electronic structure and photoluminescence (PL) properties. Moreover, loading of metal (Pt and Ag) nanoparticles, by applying the borohydride reduction method, has resulted in multicolor-emission from g-$C_3N_4$. With the help of PL spectra and local electronic structure study, at C K-edge, N K-edge, Pt L-edge and Ag K-edge by X-ray absorption spectroscopy (XAS), a precise mechanism of tunable luminescence is established. The PL mechanism ascribes the amendments in the transitions, via defect and/or metal states assimilation, between the ${\pi}^*$ states of tris-triazine ring of g-$C_3N_4$ and lone pair states of nitride. It is evidenced that interaction between the C/N 2p and metal 4d/5d orbitals of Ag/Pt has manifested a net detraction in the ${\delta}^*{\rightarrow}LP$ transitions and enhancement in the ${\pi}^*{\rightarrow}LP$ and ${\pi}^*{\rightarrow}{\pi}$ transitions, leading to broad PL spectra from g-$C_3N_4$ organic semiconductor compound.

• Clinics in Shoulder and Elbow
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• v.26 no.3
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• pp.287-295
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• 2023

Background: Posterolateral rotatory instability (PLRI) is a common mechanism of recurrent elbow instability. While the essential lesion is a deficiency in the lateral ulnar collateral ligament (LUCL), there are often associated concomitant bony lesions, such as an Osborne-Cotterill lesions (posterior capitellar fractures) and marginal radial head fractures, that compromise stability. Currently, there is no standard treatment for posterior capitellar deficiency associated with recurrent PLRI. Methods: We conducted a retrospective review of five patients with recurrent PLRI of the elbow associated with a posterior capitellar impaction fracture engaging with the radial head during normal range of motion. The patients were treated surgically with LUCL reconstruction or repair and off-label reconstruction of the capitellar joint surface using a small metal prosthesis designed for metatarsal head resurfacing (HemiCAP toe classic). Results: Five patients (three adolescent males, two adult females) were treated between 2007 and 2018. At a median follow-up of 5 years, all patients had complete relief of their symptomatic instability. No patients had pain at rest, but two patients had mild pain (visual analog scale 1-3) during physical activity. Three patients rated their elbow as normal, one as almost normal, and one as greatly improved. On short-term radiographic follow-up there were no signs of implant loosening. None of the patients needed reoperation. Conclusions: Recurrent PLRI of the elbow associated with an engaging posterior capitellar lesion can be treated successfully by LUCL reconstruction and repair and filling of the capitellar defect with a metal prosthesis. This treatment option has excellent clinical results in the short-medium term. Level of evidence: IV.

• Journal of Fashion Business
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• v.14 no.3
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• pp.1-19
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• 2010

The Assyrians usually wore two types - the tunic and the shawl. These two types were worn alone, or in combination and changes were introduced by varying the proportions of the tunic or shawl. The tunic appeared to be of the sleeves are short and reaching to the ankles or shortened to knee length according to the rank. Assyrian shawl pattern can be divided into five distinct styless. Many of the styles were suitable for costumes to wear in religious plays and pageants. Fringed shawls were the trademark of forma1 Assyrian costume. The usual badge of rank was a long fringed shawl. Intermediate rank wore shawl with short fringes and lower grade wore no shawl at all. The military costume was comparative uniformity : conical helmets was regarded as Scythic in character, short, fringed tunics, wide belts or helmet, round caps and long tunics covered in metal scales, belted at the waist. Assyrian woman costume was the long tunic with fringed hem and a long fringed shawl or was a plaid tunic and wide belt over it. They wore gold crown and horned Cap and tiara, ugal (head-dress) and the most ordinary earrings were the drop and the cross shape and necklace was made of the coloured stones and bracelets ended with heads of animal was regarded as Scythy style or adorned with a rosette at the centre.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.4
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• pp.130-140
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• 2017

Lightning protective design of an aircraft fuel system is closely related to the safety of the flight. Recently, composite material in building an aircraft becomes more important because it can reduce the weight of the aircraft. The composite materials decrease the protection against the effect of lightning. Lightning protective design of metal material aircraft has been researched for a long time and the design technique has been announced widely. However, research on the lightning protective design using composite material aircraft is very limited. In this study, lightning protective design for fuel tank structural component, access cover, fuel filler cap and drain valve in carbon fiber composite material aircraft have been presented. To show the compliance with FAA airworthiness standard regarding the presented protection designs, three steps, including lightning strike analysis, lightning environment analysis and certification test, were conducted in accordance with FAA AC 20-53.