• Journal of Welding and Joining
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• v.35 no.3
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• pp.44-51
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• 2017

In the present study, AA 5083-O plates are joined by friction stir welding technique. A universal milling machine was used to perform the welding process of the work-pieces which were fixed on the proper position by a vice. The joints were friction stir welded by two tools with different pin profiles; cylindrical threaded pin and tapered smooth one at different rotational speed values; 400 rpm and 630 rpm, and different welding speed values; 100 mm/min and 160 mm/min. During FSW of each joint, the temperature was measured by infra-red thermal image camera. The welded joints were inspected by visually as well as by the macro- and microstructure evolutions. Furthermore, the joints were tested for measuring the hardness and the tensile strength to study the effect of changing the FSW parameters on the mechanical properties. The results show that increasing the rotational speed results in increasing the peak temperature, while increasing the welding speed results in decreasing the peak temperature for the same tool pin profile. Defect free welds were obtained at lower rotational speed by the threaded tool profile. Moreover, the threaded tool pin profile gives superior mechanical properties at lower rotational speed.

• Journal of Korean Foot and Ankle Society
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• v.19 no.1
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• pp.11-17
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• 2015

Purpose: To report the radiographic and clinical results of 6.5 mm cancellous full threaded buttress screw or Steinmann pin fixation to maintain a reduction of calcaneal posterior facet depression fracture. Materials and Methods: From June 2009 to June 2012, 50 consecutive cases with calcaneal joint depression fracture that underwent open reduction and screw or pin fixation were enrolled in this study. A 6.5 mm cancellous full threaded screw was inserted from the posteroinferior aspect of the calcaneal tuberosity to the posterior facet (group A) or Steinman pin was inserted from the posterosuperior aspect of the calcaneal tuberosity to the calcaneocuboidal joint (group B). Both preoperative and postoperative Bohler and Gissane angles were measured radiographically, and American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale on the final follow-up were assessed. Results: The mean age of patients was 44.1 years, and the mean follow-up period was 27.2 months. According to the Sanders classification, 28 cases were type II and 22 cases were type III. In Sanders type II, Bohler and Gissane angles improved significantly from $10.1^{\circ}$ and $126.2^{\circ}$ preoperatively to $27.2^{\circ}$ and $117.1^{\circ}$, respectively, in the immediate postoperative radiograph, and at the final follow-up, $26.6^{\circ}$ and $118.6^{\circ}$, respectively. In Sanders type III, Bohler and Gissane angles improved significantly from $5.0^{\circ}$ and $129.8^{\circ}$ to $29.9^{\circ}$ and $119.3^{\circ}$, respectively, in the immediate postoperative radiograph, and $26.9^{\circ}$ and $120.2^{\circ}$ at the final follow-up. All cases achieved bony union, and the average period until complete union was 13.3 weeks. AOFAS ankle-hindfoot scale was 82.6 in Sanders type II and 77.3 in Sanders type III at the final follow-up. Conclusion: A 6.5 mm cancellous full threaded buttress screw or Steinman pin fixation is a noninvasive treatment method with a merit of being able to maintain the bearing capacity of the posterior facet comparable to plate fixation.

• Journal of Veterinary Clinics
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• v.24 no.4
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• pp.631-635
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• 2007

Luxation of the hip is the most common luxation seen in small animals. Luxations are classified by the direction in which the femoral head lies in relation to the acetabulum and craniodorsal luxations are the most common type. Recommendations for treatment are based on the presence of preexisting disease, the type and duration of luxation and severity of concurrent injuries. In this study modified external skeletal fixation was used for craniodorsal coxofemoral luxation in 5 dogs. Luxated head Joint was reduced and fixator pins were applied into the greater trochanter, the middle point of iliac body and the lateral surface of sacroiliac joint in a closed fashion. Reduction was successful in 4 of the 5 operated limbs. Complications noted in this study included pin tract drainage, pin loosening and secondary fracture at the pin insertion site.

• Journal of the Korean Wood Science and Technology
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• v.23 no.3
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• pp.8-15
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• 1995

This analytical study was carried out to make quality and productivity up in designing the frame-type furniture with semi-rigid joint by understanding the mechanical and structural behavior of the joint and by evaluating the validity of application of the time-saving Finite Element Method to its structural analysis. Slope deflection equation for rigid joint was modified to describe the moment-rotation behavior of semi-rigid joint and the joint stiffness factor(Z) could be calculated to lessen the experimental expense. It was proved that Finite Element Analysis with imaginary elements having equivalent MOE to the semi-rigid joint could be the alternative method for the structural analysis of the frame-type furniture, comparing the internal rotation of the 2-dimensional beam-to-column model with two-pin(wooden dowel) from the finite element method with other available theoretical and experimental rotation value.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.173-176
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• 2002

Fundamental failure mode in a laminated composite pinned joint is proposed to assess damage resulting from stress concentration in the plate. The joint area is a region with stress concentrations thus a complicated stress state exists. The modeling of damage in a laminated composite pinned joint presents many difficulties because of the complexity of the failure process. In this study, the effect on the bearing strength of the pin jointed Carbon Fiber Reinforced Plastics (CFRP) composites for magnet support structure of KSTAR tokamak with various parameters such as edge distance to diameter, width to diameter, and the temperature of $23^{\circ}C$, $-76^{\circ}C$, and $-196^{\circ}C$ was examined by comparing the experimental results with finite element analysis.

• Aerospace Engineering and Technology
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• v.12 no.1
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• pp.105-110
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• 2013

The gimbal expansion joint for the pipe line of a liquid rocket engine undergoes high pressure and cyclic rotational displacement loadings. In present study, the moment analyses and tests of the internal-type gimbal expansion joint for the engine were performed. The moment components due to spring stiffness, friction and lateral force were obtained using a analytic method and their sums at low and high pressures were compared with the test results. Also, applying a $MoS_2$ dry film lubricant to the pin of a external hinge expansion joint, it is tested that the galling of the pin was removed and the friction coefficient was decreased for low pressures.

• Journal of Korean Society of Steel Construction
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• v.10 no.4 s.37
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• pp.769-777
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• 1998

That main purpose of this paper is to clarify the effects of geometrically initial imperfection on the buckling characteristics of the pin-jointed single-layer lattice domes with triangular network. Additionally, this study is to get the data that is to formulate the general buckling-strength equation taking geometrically initial imperfection into consideration. Analysis is undertaken by using the frame analysis method which is based on the finite element method dealing with geometrically nonlinear problem.

• Journal of Korean Neurosurgical Society
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• v.37 no.4
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• pp.293-295
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• 2005

Posterior interosseous nerve(PIN) syndrome is an entrapment of the deep branch of the radial nerve just distal to the elbow joint. It is caused by acute trauma or masses compressing the nerve. We report an unusual case of PIN syndrome with wrist drop caused by compression of the nerve by anomalous vascular leash. The patient has recovered with the surgical decompression of the offending vessels and arcade of Frohse.

• Journal of Ocean Engineering and Technology
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• v.18 no.5
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• pp.36-42
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• 2004

Orthotropic laminates, such as [$0^{\circ}6$/$90^{\circ}6$]s and [$90^{\circ}6$/$0^{\circ}6$]s, were performed, using a commercial nonlinear finite element method. Interlaminar stress distributions, around the hole curve free-edge, were calculated. The delamination bearing strengths of pin joints were predicted, using the modified delamination failure criterion. These stress distributions were presented along the radial lines and around the free-edge of the hole. Further, three-dimensional non-linear contact analysis of orthotropic laminates was conducted to investigate the effect of friction. In this paper, laminates with a circular hole were taken to study interlaminar stresses the curved edge. This study may assist in the design of a thick composite laminate with mechanically pin joints.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1289-1294
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• 2008

Electrostatic discharge(ESD) phenomenon is a serious reliability concern. It causes approximately most of all field failures of IC. To quality the ESD immunity of IC product, there are some test methods and standards developed. ESD events have been classified into 3 models, which are HBM, MM and CDM. All the test methods are designed to evaluate the ESD immunity of IC products. This study provides an overview among ESD test methods on ICs and an efficient ESD stress method. We have estimated on all pin combination about the positive and negative ESD stress. We make out the weakest stress mode. This mode called a worst-case mode. We proposed that positive supply voltage pin and I/O pin combination is efficient because it is a worst-case mode.