• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.394-396
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• 2004

In order to reduce the sheath circulating current, same arrangement and balanced length of cable are required for the underground cable system. But practically, changing the whole arrange of cable which is already constructed is impossible. Therefore, It is necessary to apply the restraining-unit of sheath circulating current at the cross-bonding wire of insulated joint because the impedance of restraining-unit is able to reduce sheath circulating current at a normal condition. Even at a transient state, the restraining-unit must maintain electrical and mechanical characteristics. In this paper, the features of restraining-unit developed by LG Cable as well as the electrical test results are described. It proves that the restraining-unit is applicable to the underground cable system where sheath circulating current rises.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1995년도 춘계학술대회논문집
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• pp.170-177
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• 1995

The restraining characteristics for the single square drawbead are discussed. The drawbead restraining forces adn maximum strains by the various drawing angles are measured experimentally. During this procedure , the drawing angles are varied from 0$^{\circ}C$ to 60$^{\circ}C$. Also, the wide range of experimental data of the drawing forces and maximum strains for the various drawbead dimensions, dimensions, clearances and blank holding forces are preseted.

• 소성∙가공
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• 제7권1호
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• pp.12-22
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• 1998

An expert drawbead model is developed for the finite element analysis of stamping processes. The expert model calculates drawbead restraining forces and bead-exit thinnings with the forming condi-tions and drawbead size. The drawbead restraining forces and bead-exit thinnings of a circular draw-bead and stepped drawbead are computed by mathematical models and corrected by the multiple lin-ear regression method based on experimental measurements. The squared drawbead preventing the sheet from drawing-in inside die cavity is assumed to have a very huge drawbead restraining force and no pre-strain just after drawbead. The combined beads are considered as a combination of basic draw-beads such as circular a drawbead stepped drawbead and squared drawbead so that the drawbead restraining forces and bead-exit thinnigs are basically sum of those of basic drawbeads.

• Steel and Composite Structures
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• 제23권2호
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• pp.217-228
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• 2017

Braces are one of the retrofitting systems of structure under earthquake loading. Buckling restrained braces (BRBs) are one of the very efficient braces for lateral loads. One of the key needs for a desirable and acceptable behavior of buckling-restraining brace members under intensive loading is that it prevents total buckling until the bracing member tolerates enough plastic deformation and ductility. This paper presents the results of a set of analysis by finite element method on buckling restrained braces in which the filler materials within the restraining member have been removed. These braces contain core as the conventional BRBs, but they have a different buckling restrained system. The purpose of this analysis is conducting a parametric study on various empty spaces between core and restraining member, the effect of friction between core and restraining member and applying initial deformation to brace system to investigate the global buckling behavior of these braces. The results of analysis indicate that the flexural stiffness of restraining member, regardless of the amount of empty space, can influence the global buckling behavior of brace significantly.

• The Korean Journal of Physiology and Pharmacology
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• 제18권2호
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• pp.103-108
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• 2014

Head restraining is an experimental technique that firmly secures the animal's head to a fixation apparatus for the precise control and sensing of behaviors. However, procedural and surgical difficulties and limitations have been obstructing the use of the technique in neurophysiological and behavioral experiments. Here, we propose a novel design of the head-restraining apparatus which is easy to develop and convenient for practical use. Head restraining procedure can be completed by sliding the head mounter, which is molded by dental cement during implantation surgery, into the port, which serves as matching guide rails for the mounter, of the fixation bar. So neither skull-attached plates nor screws for fixation are needed. We performed intracranial self stimulation experiment in rats using the newly designed device. Rats were habituated to acclimatize the head-restraint environment and trained to discriminate two spatially distinguished cues using a customized push-pull lever as an operandum. Direct electrical stimulation into the medial forebrain bundle served as reward. We confirmed that head restraining was stable throughout experiments and rats were able to learn to manipulate the lever after successful habituation. Our experimental framework might help precise control or sensing of behavior under head fixed rats using direct electrical brain stimulation as a reward.

• 한국구조물진단유지관리공학회 논문집
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• 제5권3호
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• pp.131-139
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• 2001

Experimental programs were accomplished to improve and evaluate the structural performance of RC frame structures with masonry infilled wall, such as the hysteretic behavior, the maximum horizontal strength, crack propagation, and ductility etc. Test variables are restraining factors of frame, with or without masonry infilled wall, and masonry method. Six reinforced concrete rigid frame and masonry infilled wall were tested and constructed in one-third scale size under vertical and cyclic loads simultaneously. Based on the test results, the following conclusions can be made. For masonry infilled wall with restraining factors of frame(IFWB-1~3), cumulated energy dissipation capacities were increased by 1.35~1.60 times in comparision with that of masonry infilled wall(IFB-1) at final stage of testing. For masonry infilled wall with restraining factors of frame, maximum horizontal capacities were increased by 1.91~2.24 times in comparision with that of rigid frame.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.541-546
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• 2001

Experimental programs were accomplished to improve and evaluate the structural performance of test specimens, such as the hysteretic behavior, the maximum horizontal strength, crack propagation of and ductility etc. Test variables are restraining factors of frame, with or without masonry infilled wall, and masonry method Six reinforced concrete rigid frame and masonry infilled wall were tested and constructed in one-third scale size under vertical and cyclic loads simultaneously. Based on the test results, the following conclusions can be made. For masonry infilled wall with restraining factors of frame, maximum horizontal capacities were increased by 1.91~2.24 times in comparision with that of rigid frame. For masonry infilled wall with restraining factors of frame(IFWB-l~3), cumulated energy dissipation capacities wear increased by 1.35~l.60 times in comparision with that of masonry infilled wall(IFB-1) at final stage of testing.

• 소성∙가공
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• 제7권1호
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• pp.36-48
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• 1998

In order to analyze the stretch flange forming characteristics of tailored blanks. laser welded blanks of different thickness and strength combinations were prepared and hole expansion tests were done. The stretch flange formability of laser welded blanks was reduced as increasing the deformation restraining force($strength{\times}thickness$) ratio between two welded sheets. Simulation of stretch forming mode deformation and comparson with experimental results showed that the stretch flange formabili-ty was influenced not only by the difference of the deformation restraining forces between two base sheets but also by the difference of the deformation restraining forces between base sheet and weld. Therefore the stretch flange formability was reduced more rapidly than tensile elongation as increas-ing the deformation restraining force ration. It was also found that simulation of stretch flange forming was more accurate when material properties of weld was given.

• 소성∙가공
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• 제3권4호
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• pp.454-467
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• 1994

The drawbead restraining forces for the various radius of drawbead and die corner are analyzed by the belt theory, and they are compared with the experimental results. During this procedure, the drawing angles are also varied from $0^{\circ}$ to $60^{\circ}$, and the near part of the drawed die corner are divided into fur steps for the theoretical analysis. The stress distributions through the sheet thickness for these steps are also suggested theoretically. The wide range of experimental data of the drawing forces and strain distributions for the various dimension and blank holding forces are presented. It is concluded that the theoretical assumption for the restraining force analysis is very useful from the comparison with the experimental results.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 추계학술대회 논문집
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• pp.87-90
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• 2005

The drawbead is used to control the material flow into the die and increase the forming quality during the binder wrap process and the stamping process in the sheet metal forming. Drawbead restraining force (DBRF) is controlled by geometrical parameters and influenced by process parameters such as friction coefficient and blank thickness. In order to inspect the effect of process parameters, parameter studies are performed with the variation of parameters using finite element model of drawbead which is utilized reliably for the calculation of the drawbead restraining force. Drawbead analysis is carried out with 2-D plane-strain element and 3-D shell element. After the verification of the accuracy of the drawbead model with 3-D shell element, it is utilized to the prediction and the investigation of the effect of process parameters. The result of parameter studies can be utilized to the die design in the tryout stage.