• Restorative Dentistry and Endodontics
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• v.39 no.3
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• pp.226-229
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• 2014

Orthodontic extrusion is usually performed by means of a fixed orthodontic appliance that utilizes arch wire attached to adjacent teeth and transfers the desired force by elastic from the wire to the root. However, clinicians often encounter cases where the bonding required for tooth traction is not possible because the adjacent teeth have been restored with ceramic or veneer. The purpose of this case report is to describe a modified orthodontic extrusion appliance that is useful when conventional orthodontic treatment is not possible. The modified appliance was fabricated using an artificial tooth, clear plastic sheeting, and a braided fiber-reinforced composite strip that covered adjacent teeth without bonding. It satisfied the esthetic and functional needs of the patient and established the optimal biologic width.

• Elastomers and Composites
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• v.34 no.4
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• pp.299-314
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• 1999

Bonding metal and textile components to rubber has always posed a problem. In this paper, an attempt had been made to modify textile and metal surfaces for bonding with rubber. The metal surfaces were modified using silane coupling agents and textile fibers were modified using plasma polymerization techniques. Some results on adhesion of metals to a range of sulfur-cured rubber compounds using a combination of organofunctional silanes are given here. The treatment was not only effective for high-sulfur compounds but also for low-sulfur com pounds as used in engine mounts and even for some semi-EV compounds. Coatings of plasmapolymerized pyrrole or acetylene were deposited on aramid and polyester tire cords. Standard pull-out force adhesion measurements were used to determine adhesion of tire cords to rubber compounds. The plasma coatings were characterized by various techniques and the performance results are explained in an interpenetrating network model.

• Journal of the Semiconductor & Display Technology
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• v.7 no.1
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• pp.41-45
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• 2008

We studied the electrical characteristics of low-k SiOCR interlayer dielectric(ILD) films fabricated by plasma enhanced chemical vapor deposition (PECVD). The precursor bis-trimethylsilylmethane (BTMSM) was introduced into the reaction chamber with the various flow rates. The absorption intensities of Si-O-$CH_x$, bonding group and Si-$CH_x$, bonding group changed synchronously for the variation of precursor flow rate, but the intensity of Si-O-Si(C) responded asynchronously with the $CH_x$, combined bonds. The SiOCH films revealed ultra low dielectric constant around 2.1(1) and reduced further below 2.0 by heat treatments.

• Journal of Welding and Joining
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• v.22 no.3
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• pp.62-68
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• 2004

The strip Au bumps are bonded using longitudinal ultrasonic far the electronic package. Au bumps on the chip and substrate are aligned in a crossed shape, and the ultrasonic is imposed on the chip to form the solid-state bond between the Au bumps. Deformed bump shapes are calculated using the finite element method, and the bond strength is measured experimentally. The crossed strip Au bumps are deformed similar to the saddle, which provides larger contact surface area and higher friction force. Compared with the previous bonding method between the Au bump and planar pad, higher bond strength is obtained using the crossed strip bumps.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.15-16
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• 2022

In order to examine the adhesion characteristics of road pavement according to environmental conditions, the freezing time of cement mortar and the adhesion performance between ice and pavement were evaluated depending on the presence or absence of polymer and water repellent. As a result of measuring the ice formation time, it was found that there was no delay when a polymer was added, but the complete freezing time was delayed when a water repellent was added. As a result of measuring the strength of ice adhesion, it was found that the bonding force between ice and the surface of the test body was greatly generated in the test body without water repellent. In the case of a test specimen to which a water repellent was added, it was found that the bonding strength between the test specimen surface and ice was reduced.

• The korean journal of orthodontics
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• v.42 no.1
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• pp.39-46
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• 2012

Objective: We evaluated the detachment force, amount of deformation, fracture mode, and pull-out force of 3 different wires used for bonded lingual retainer fabrication. Methods: We tested 0.0215-inch five-stranded wire (PentaOne, Masel; group I), $0.016{\times}0.022$-inch dead-soft eight-braided wire (Bond-A-Braid, Reliance; group II), and 0.0195-inch dead-soft coaxial wire (Respond, Ormco; group III). To test detachment force, deformation, and fracture mode, we embedded 94 lower incisor teeth in acrylic blocks in pairs. Retainer wires were bonded to the teeth and vertically directed force was applied to the wire. To test pull-out force, wires were embedded in composite that was placed in a hole at the center of an acrylic block. Tensile force was applied along the long axis of the wire. Results: Detachment force and mode of fracture were not different between groups. Deformation was significantly higher in groups II and III than in group I (p < 0.001). Mean pull-out force was significantly higher for group I compared to groups II and III (p < 0.001). Conclusions: Detachment force and fracture mode were similar for all wires, but greater deformations were seen in dead-soft wires. Wire pull-out force was significantly higher for five-stranded coaxial wire than for the other wires tested. Five-stranded coaxial wires are suggested for use in bonded lingual retainers.

• Structural Engineering and Mechanics
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• v.16 no.5
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• pp.519-531
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• 2003

Piezoelectric actuators have long been recognised for use in aerospace structures for control of structural shape. This paper looks at active control of the swept shock wave/turbulent boundary layer interaction using smart flap actuators. The actuators are manufactured by bonding piezoelectric material to an inert substrate to control the bleed/suction rate through a plenum chamber. The cavity provides communication of signals across the shock, allowing rapid thickening of the boundary layer approaching the shock, which splits into a series of weaker shocks forming a lambda shock foot, reducing wave drag. Active control allows optimum control of the interaction, as it would be capable of positioning the control region around the original shock position and unimorph tip deflection, hence mass transfer rates. The actuators are modelled using classical composite material mechanics theory, as well as a finite element-modelling program (ANSYS 5.7).

• International Journal of Highway Engineering
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• v.18 no.1
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• pp.85-90
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• 2016

PURPOSES : The objective of this paper is to understand the deterioration phenomenon and causes in the pavement of a ramp area. METHODS : Ramp areas need to be sloped because of the centrifugal force, which depends on the vehicle speed and grade of the ramp area. As a result, vertical and horizontal forces are applied on the pavement surface of the ramp area. Furthermore, the horizontal force depends on the vehicle speed and grade of the ramp area. In order to analyze the pavement structure of a ramp area, a multi-layered elastic analysis program was used to evaluate the weakest link of fatigue cracking deterioration, according to the simultaneously applied vertical and horizontal forces. RESULTS : From case studies related to the bonding conditions between the surface and base layer in a ramp area, it was found that the partially bonded cases resulted in a critical potential of fatigue cracking deterioration, in a comparison of 50%, 70%, and fully bonded cases. CONCLUSIONS : According to the results of the case studies, the pavement structure system should be reinforced by upgrading the material or increasing the thickness compared to the general pavement areas, in order to provide a performance life similar to the mainline pavements in the ramp areas.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.5
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• pp.140-147
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• 2008

In this study, a carbon nanotube probe (CNT probe) is proposed as a mechanical force transducer for the measurement of pico-Newton (pN) order force in biological applications. In order to measure nantube's displacement in the air or liquid environment, the fabrication of a CNT probe with tip-specific loading of fluorescent dyes is performed using tip- specific functionalization of the nanotube and chemical bonding between dyes and nanotube. Also, we experimentally investigated the mechanical properties of the CNT probe using electrostatic actuation and fluorescence microscope measurement. Using fluorescence measurement of the tip deflection according to the applied voltage, we optimized the bending stiffness of the CNT probe, therefore determined the spring constant of the CNT probe. The results show that the spring constant of CNT probes is as small as 1 pN/nm and CNT probes can be used to measure pN order force.

• Korean Journal of Metals and Materials
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• v.47 no.4
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• pp.261-266
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• 2009

The mechanical and electrical properties of ball grid array (BGA) solder joints were measured, consisting of Sn-3.5Ag, with organic solderability preservative (OSP)-finished Cu pads and Electroless Nickel/Immersion Gold (ENIG) surface finishes. The mechanical properties were measured by die shear test. When ENIG PCB was upper joint and OSP PCB was lower joint, the highest shear force showed at the third reflow. When OSP PCB was upper joint and ENIG PCB was lower joint, the highest shear force showed at the forth reflow. For both joints, after the die shear results reached the highest shear force, shear force decreased as a function of increasing reflow number. Electrical property of the solder joint decreased with the function of increasing reflow number. The scanning electron microscope results show that the IMC thickness at the bonding interface gets thicker while the number of reflow increases.