• Steel and Composite Structures
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• v.46 no.3
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• pp.417-433
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• 2023

The maximum ductility and cumulative ductility of connection joints of Buckling-Restrained Braced Frames (BRBF) are critical to the structural overall performance, which should be matched with the BRB ductility. The two-story and one-span BRBF with a one-third scale was tested under cyclic quasi-static loading, and the top-flange beam splice (TFBS) rotational connections were proposed and adopted in BRBF. The deformation capacity of TFBS connections was observed during the test, and the relationship between structural global ductility and local connection ductility was studied. The rotational capacity of the beam-column connections and the stability performance of the BRBs are highly relevant to the structural overall performance. The hysteretic curves of BRBF are stable and full under large displacement demand imposed up to 2% story drift, and energy is dissipated as the large plastic deformation developed in the structural components. The BRBs acted as fuses and yielded first, and the cumulative plastic ductility (CPD) of BRBs is 972.6 of the second floor and 439.7 of the first floor, indicating the excellent energy dissipation capacity of BRBs. Structural members with good local ductility ensure the large global ductility of BRBF. The ductile capacity and hysteretic behavior of BRBF with TFBS connections were compared with those of BRBF with Reduced Beam Section (RBS) connections in terms of the experimental results.

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.2
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• pp.308-329
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• 1997

A lot of the research paper was reported about the result of influence of IMC (Intra-mobile connector) in the IMZ implant placed solely in the alveolar bone, but reports about the effect of IMC on functional load at state of connecting with natural teeth ere rare. The major propose of this study was find the mechanical character of IMC itself by using the finite element analysis program after simulated variance of condition connected with the natural teeth and implant on funcional load. When first and second premolar was lost, IMZ implant was placed with a diameter of 3.3mm and a length of 13mm with IMC in second premolar area. Rigid connection was done and the non-figid connention was located on the female part of the canine abutment and the implant respectively and then both the infraocclusion of $30{\mu}m$ and the non-infraocclusion under the load of 40kg applied to the portion of the natural teeth, the pontic and the implant. The displacement and the stress of it was estimated and analyzed IMC itself of the rigid connection and the non-rigid connection was grouped. The following result were obtained. 1. In all groups, the displacement of Y-axis was greater than that of X-axis and the aspect of displacement showed that IMC was displaced downward and to the center. 2. There was no differences in the displacement of IMC regardless of the connection type. 3. In the displacement of IMC, I 4 was the least, I 1 and I 3 are similar and I 2 was the greatest. 4. There was no differences in the peak value of maximal stress of IMC regardless of the connection type. 5. In the peak value of maximal stress of IMC, I 4 was the least, I 1 and I 3 were similar, and I 2 was the largest.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.3
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• pp.251-257
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• 2017

Purpose: The purpose of this study was to evaluate whether the internal abutment length affected screw stability in an internal connection implant. Materials and methods: Twenty long internal connection implants (Replus system, $4.7{\times}11.5mm$) were selected for this investigation. Abutments were assigned to four groups depending on the length of the internal connection (abutments with internal lengths of 1, 2, 3, and 4 mm, respectively). Each implant fixture specimen was embedded in resin medium and connected to an abutment with an abutment screw. A load of 100 N, applied at an angle of $30^{\circ}$ to the long axis of the implant, was repeated for $1.0{\times}10^6$ cycles. Reverse torque values (RTV) were recorded before and after loading, and the change in RTV was calculated. Data were analyzed with the Kruskal-Wallis test. Results: The change in RTV was not significantly different among the groups (P>.05). Screw loosening and fractures were not observed in any groups, and joint stability was maintained. Conclusion: The internal length of the abutment may not significantly affect the degree of screw loosening.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.2
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• pp.110-119
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• 2016

Purpose: This study is aimed to assess changes of stress distribution dependent on different connection lengths and placement of the fixture top relative to the ridge crest. Materials and methods: The internal-conical connection implant which has a hexagonal anti-rotation index was used for FEM analysis on stress distribution in accordance with connection length of fixture-abutment. Different connection lengths of 2.5 mm, 3.5 mm, and 4.5 mm were designed respectively with the top of the fixture flush with residual ridge crest level, or 2 mm above. Therefore, a total of 6 models were made for the FEM analysis. The load was 170 N and 30-degree tilted. Results: In all cases, the maximum von Mises stress was located adjacent to the top portion of the fixture and ridge crest in the bone. The longer the connection length was, the lower the maximum von Mises stress was in the fixture, abutment, screw and bone. The reduction rate of the maximum von Mises stress depending on increased connection length was greater in the case of the fixture top at 2 mm above the ridge crest versus flush with the ridge crest. Conclusion: It was found that the longer the connection length, the lower the maximum von Mises stress appears. Furthermore, it will help prevent mechanical or biological complications of implants.

• The Journal of Advanced Prosthodontics
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• v.6 no.1
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• pp.35-38
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• 2014

PURPOSE. This study aimed to evaluate the correlation between microleakage and screw loosening at different types of implant-abutment connections and/or geometries measuring the torque values before and after the leakage tests. MATERIALS AND METHODS. Three different abutment types (Intenal hex titanium, internal hex zirconium, morse tapered titanium) with different geometries were connected to its own implant fixture. All the abutments were tightened with a standard torque value then the composition was connected to the modified fluid filtration system. After the measurements of leakage removal torque values were re-measured. Kruskal-wallis test was performed for non-parametric and one-way ANOVA was performed for parametric data. The correlation was evaluated using Spearman Correlation Test (${\alpha}=0.05$). RESULTS. Significantly higher microleakage was found at the connection of implant-internal hex zirconium abutment. Observed mean torque value loss was also significantly higher than other connection geometries. Spearman tests revealed a significant correlation between microleakage and screw loosening. CONCLUSION. Microleakage may provoke screw loosening. Removing torque values rationally decrease with the increase of microleakage.

• The Mathematical Education
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• v.51 no.4
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• pp.471-484
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• 2012

It is not easy to find the auxiliary line to solve the problem in connection with the circle, where it is the problem finding the central angle or angle at the circumference in a circle. The purpose of the study is to give an aid for this difficulties. The angle at the circumference is closely related to the arc. And so we looked into the problem in connection with the angle at the circumference in point of view of the arc. We have got the following the results. It is not necessary to draw the auxiliary line when solving the problem in connection with the angle at the circumference in point of view of the arc. And we can find the reason to draw the specific auxiliary in point of view of the arc. We hope that the results of research are given aids to a lot of students.

• Journal of Advanced Engineering and Technology
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• v.11 no.4
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• pp.279-285
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• 2018

A shear connection between the steel beam and concrete slab determines the stability of composite beams. An extensive numerical study to evaluate the resistance of the shear connection in a solid slab at high temperature was conducted. Three-dimensional thermo-mechanical finite element models were developed using a dynamic explicit method and concrete damaged plasticity model. Temperature-dependent plasticity parameters of the concrete model were proposed, and the accuracy of the developed model was obtained against experimental data. This investigation has revealed that a stud shearing failure occurs regardless of temperatures, and its shearing location changes in accordance with a rise in temperature. A new strength reduction formula has been presented to estimate the resistance of the shear connection at high temperatures.

• Journal of Korean Association for Spatial Structures
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• v.23 no.1
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• pp.69-76
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• 2023

A timber lattice roof, which has around 30m span, was constructed. In order to figure out the realistic buckling load level, the structural analysis of this roof structure was performed especially by stiffness of connection with various asymmetric snow load. Due to the characteristics of application of snow load, the load combinations of snow should be considered not only global area but also local part so that the critical buckling load could be observed as easy as possible. Geometrical imperfection was simulated to consider inaccurate shape of structure. And then nonlinear analysis were performed. Finally, this paper could investigate that the asymmetric snow load with the lower level stiffness of connection decreased the level of buckling load significantly.

• JSTS:Journal of Semiconductor Technology and Science
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• v.10 no.1
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• pp.28-36
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• 2010

Hardware implementation methods for Artificial Neural Network (ANN) have been researched for a long time to achieve high performance. We have proposed a Network on Chip (NoC) for ANN, and this architecture can reduce communication load and increase performance when an implemented ANN is small. In this paper, a multiple NoC models are proposed for ANN, which can implement both a small size ANN and a large size one. The simulation result shows that the proposed multiple NoC models can reduce communication load, increase system performance of connection-per-second (CPS), and reduce system running time compared with the existing hardware ANN. Furthermore, this architecture is reconfigurable and reparable. It can be used to implement different applications of ANN.

• Steel and Composite Structures
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• v.42 no.4
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• pp.569-590
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• 2022

This paper presents a combined experimental and numerical study on stainless steel end-plate connections, with an emphasis placed on their ultimate behaviour and rotation capacity. In the experimental phase, six connection specimens made of austenitic and lean duplex stainless steels are tested under monotonic loads. The tests are specifically designed to examine the close-to-failure behaviour of the connections at large deformations. It is observed that the rotation capacity is closely related to fractures of the stainless steel bolts and end-plates. In the numerical phase, an advanced finite element model suitable for fracture simulation is developed. The incorporated constitutive and fracture models are calibrated based on the material tests of stainless steel bolts and plates. The developed finite element model exhibits a satisfactory accuracy in predicting the close-to-failure behaviour of the tested connections. Finally, the moment resistance and rotation capacity of stainless steel end-plate connections are assessed based on the experimental tests and numerical analyses.