• Nuclear Engineering and Technology
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• v.53 no.3
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• pp.932-941
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• 2021

This paper suggests a fracture simulation method for SFR metallic fuel pin under accident condition. Two major failure mechanisms - creep damage and eutectic penetration - are implemented in the suggested method. To simulate damaged element, stress-reduction concept to reduce stiffness of the damaged element is applied. Using the proposed method, the failure size of cladding can be predicted in addition to the failure time and failure site. To verify the suggested method, Whole-pin furnace (WPF) test and TREAT-M test conducted at Argonne National Laboratory (ANL) are simulated. In all cases, predicted results and experimental results are overall in good agreement. Based on the simulation result, the effect of eutectic-penetration depth representing failure behavior on failure size is studied.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.1
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• pp.147-152
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• 2008

This paper has been fabricated the two different type of variable attenuators using a characteristics of a 3 dB directional coupler and pin diodes. One was not analyzed using the conventional even-odd modes but used simple two-port techniques. The resulting scattering parameters described operation characteristics for the general case where the terminating impedances are equal and unequal. After analyzing resistor role of the ${\pi}$ type fixed attenuator. this paper used a pin diode instead of a resistor. The variable attenuators were fabricated using pin diodes for current-controlled attenuation on the coupled ports of a 3 dB branch-line coupler and ${\pi}$ type fixed attenuator. The realized variable attenuators have more than 33 dB attenuation ranges at 2.1 GHz. and the input and output reflection coefficients are less than -13 dB. These results could be applied to mobile communication systems. It can be varied gain of the power amplifier according to change a outdoor environmental temperature and improved linearity.

• Journal of Satellite, Information and Communications
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• v.10 no.3
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• pp.26-31
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• 2015

This paper deals with a size-reduced Ku-band waveguide limiter. Basically, it passes the signal from 16.125 GHz through 16.375 GHz, but when excessively high power is injected to the input port, it should change to a bandstop filter. Furthermore, it is required to change to bring attenuation by more than 20 dB and 50 dB over a narrow band and the entire passband, respectively. Therefore, in order to meet this requirement, a limiting device is implemented with multiple PIN-diode posts that enable the limiter to be the bandpass filter and stopband one at the off and on states of the PIN-diode switch, respectively. So, the design goes through the equivalent circuit modelling and the geometry is realized in the accurate electromagnetic analysis CAD tool. Finally, the result is discussed to shed light on whether it complies with the aforementioned requirement.

• Korean Journal of Veterinary Research
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• v.63 no.3
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• pp.24.1-24.6
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• 2023

This study compared the biomechanical properties of bone-stapling techniques with those of other fixation methods used for stabilizing tibial tuberosity fractures using 3-dimensionally (3D)-printed canine bone models. Twenty-eight 3D-printed bone models made from computed tomography scan files were used. Tibial tuberosity fractures were simulated using osteotomy. All samples were divided into 4 groups. Group 1 was stabilized with a pin and tension-band wire; group 2, with a pin and an 8 mm-wide bone staple; group 3, with 2 horizontally aligned pins and an 8 mm-wide bone staple; and group 4 with a 10 mm-wide bone staple. Tensile force was applied with vertical distraction until failure occurred. The load and displacement were recorded during the tests. The groups were compared based on the load required to cause displacements of 1, 2, and 3 mm. The maximum failure loads and modes were recorded. The loads at all displacements in group 4 were greater than those in groups 1, 2, and 3. The loads at 1, 2, and 3 mm displacements were similar in groups 1 and 3. There was no significant difference between groups 1 and 3. Groups 1 and 4 provided greater maximum failure loads than groups 2 and 3. Failure occurred because of tearing of the nylon rope, tibial fracture, wire breakage, pin bending, and fracture around the bone staple insertion. In conclusion, these results demonstrate that the bone-stapling technique is an acceptable alternative to tension-band wire fixation for the stabilization of tibial tuberosity fractures in canine bone models.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.313-318
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• 2001

The sliding wear behavior of Plasma-Sprayed Al$_2$O$_3$-TiO$_2$ Coating against Cemented Carbide were Investigated using a pin on disk type tester. The experiment was conducted using Al$_2$O$_3$-TiO$_2$ Coaling as pin material and Cemented Carbide as disk material and different operating conditions, at room temperature under a dry conditions. The results showed that the type B(250kw power) appeared average wear rate Is lowed than type A(80kw power). The specific wear rate of Specimen A1 Increased with normal load. But The specific wear rate of Specimen B1 decreased with normal load. Average wear rate of specimen A3, B3 are lowed than other but the sliding wear mechanism of edge were rough.

• Tribology and Lubricants
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• v.33 no.3
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• pp.98-105
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• 2017

A pin-on-disk test is performed to measure the wear volume of a ductile cast iron (DCI) roll when it wears down using a high carbon steel and two alloy steels at different sliding velocities between the roll and the material (steel). Normal pressure is set as constant and test temperatures are 400, 500 and $600^{\circ}C$. In addition, thermal softening behavior of the DCI roll is examined using a high-temperature micro-hardness tester and the surface hardness variation of the DCI roll is expressed in terms of temperature and heating time. Based on experimental data, a wear coefficient used in Archard's wear model for each material is obtained. The wear volume is clearly observed when the test temperature is $400^{\circ}C$ and sliding velocity varies. However, it is not measured at temperatures of $500^{\circ}C$ and $600^{\circ}C$ even with variations in sliding velocity. From the optical photographs of the pin and disk, the abrasive wear is observed at $400^{\circ}C$ clearly, but no at $500^{\circ}C$ and $600^{\circ}C$. At higher temperatures, the pin surface is not smooth and has many tiny caves distributed on it. It is found that wear volume is dependent on the carbon contents rather than alloy contents. Results also reveal that the variations of wear coefficients are almost linearly proportional to the carbon contents of the material.

• The Journal of Korean Academy of Prosthodontics
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• v.28 no.2
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• pp.77-90
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• 1990

The purpose of this study was to compare the amount of the vertical pin opening of $33^{\circ}$ resin and $0^{\circ}$ resin teeth during processing and to determine whether the changes in tooth contacts by using articulation ribbon and T-Scan system follow any identifiable pattern, and to determine if there is any correlation between the changes in tooth contacts and the amount of the vertical pin opening after processing. Through statistical analyses on the data from this study, the following conclusions were obtained. 1. The amounts of the vertical pin opening were 0.78m, 0.87mm for $0^{\circ}$ teeth and $33^{\circ}$ teeth, respectively. But there was no significant difference between them. 2. The total number of contact points recorded by articulating ribbon after processing was decreased to 442.5% of that before processing. 3. The mean values for the number of contact points per tooth recorded by articulating ribbon after processing were 4.3 for the second molar, 3.8 for the first molar, 1.3 for the second premolar, 0.8 for the first premolar. The reduction of contact points per tooth became greater moving in an anterior direction. 4. The correlation between the reduction of contact points and the amount of the pin opening after processing was not significant. 5. The mean values for the numbers of contact points per tooth recorded by T-Scan system after processing were 2.2, 2.5, 1.0, and 0.5 at the second molar, the first molar, the second premolar, and the first premolar, respectively. 6. The correlation between the number of contact points by using articulating ribbon and TScan system after processing was not significant.

• Composites Research
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• v.25 no.3
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• pp.65-69
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• 2012

The main objective of this study is to investigate the effect of metal z-pinning on the failure behavior of cocured composite single-lap joints. Three different pin diameters (0.3, 0.5, and 0.7 mm) and three pin areal densities (0.5, 2.0, and 4.0%) were examined. The specimens were fabricated by T700-12K-31E#2510 unidirectional prepreg from Toray. Stainless steel pins were used for z-pinning. Test results showed that except one case with extremely low pin density of 0.5%, all other z-pinned joints exhibited lower initial crack stresses than those of the unpinned joint. However the ultimate strength of the z-pinned joint increased up to 45% at most. Furthermore, even after the complete failure of the joint, the z-pins sustained the carried load to a certain degree experiencing large deformation and provided the stable fracture behavior for the composite joint.

• Imaging Science in Dentistry
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• v.41 no.3
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• pp.115-121
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• 2011

Purpose : This article is to describe a modified device for intraoral radiography which was developed to obtain reproducible radiographic images for assessment of distal osseous defects of the mandibular second molar (2 Mm) after impacted third molar (3 Mm) surgery. Materials and Methods : A commercial available alignment system for posterior region was modified by adding a reference gauge pin (millimetric) and threading a hollow acrylic cylinder at the ring of the radiographic positioner to attach the X-ray collimator. The design included customized resin acrylic stent for the occlusal surface of the 2Mm in maximum intercuspal position, individualizing the biteblock positioner. Periapical radiographs were taken before and after surgical extraction of 3 Mm, employing the radiographic technique of parallelism described by Kugelberg (1986) with this modified film holder and inserting the gauge pin on the deepest bone probing depth point. Results : This technique permitted to obtain standardized periapical radiographs with a moderate to high resolution, repeatability, and accuracy. There was no difference between the measurements on the pre- and post-operative radiographs. This technique allowed better maintenance of the same geometric position compared with conventional one. The insertion of the gauge pin provided the same reference point and localized the deepest osseous defect on the two-dimensional radiographs. Conclusion : This technique allowed better reproducibility in posterior radiographic records (distal surface of 2 Mm) and more accurate measurements of radiographic bone level by the use of a millimetric pin.

• Fashion & Textile Research Journal
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• v.11 no.3
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• pp.474-480
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• 2009

The purpose of this study is to prepare the hardness of polyester(PET) fabric by thermal bonding with low melting component of bicomponent fiber and to describe the change of physical properties of thermal bonded PET fabrics. The PET fabrics were prepared with regular PET fiber as warp and bicomponent fiber as weft. The bicomponent fiber of sheath-core type were composed with a regular PET core and low melting PET sheath. The thermal bonding of PET fabric was carried out in pin tenter from 120 to $195^{\circ}C$ temperature range for 60 seconds. In this study, we investigated the physical properties and melting behavior of PET fiber and the effect of the temperature of the pin tenter on the thermal bonding, mechanical properties. Melting peak of warp showed the thermal behavior of general PET fiber. However, melting peak of weft fiber(bicomponent fiber) showed the double melting peak. The thermal bonding of the PET fabric formed at about temperature of lower melting peak. The optimum thermal bonding conditions for PET fabrics was applied at $190{\sim}195^{\circ}C$ for 60seconds by pin tenter. On the other hand, the tensile strength of the PET fabric decreased with an increasing temperature of thermal bonding.