• Steel and Composite Structures
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• v.42 no.3
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• pp.315-323
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• 2022

Shear connectors are key elements that ensure integrity in a composite system. The primary purpose of a shear connector is to bring a high degree of interaction between composite elements. A wide variety of connectors are available for hot-rolled composite construction, connected to the beam through welding. However, with cold-formed members being very thin, welding of shear connectors is not desirable in cold-formed composite constructions. Shear connectors for cold-formed elements are limited in studies as well as in the market. Hence in this study, three different types of shear connectors, namely, single-channel, double channel, and self-tapping screw, were considered, and their performance assessed by the Push-out test as per Eurocode 4. The connection between channel shear connectors and the beam was made using self-tapping screws to avoid welding. The performance of the connectors was analyzed based on their ultimate capacity, characteristic capacity, ductility, and slippage during loading. Strength to weight ratio was also carried out to understand the proposed connectors' suitability for conventional ones. The results showed relatively higher initial stiffness and ductility for double channel connectors than other connectors. Also, self-tapping screws had a higher strength to weight ratio with low ductility.

• Korean Journal of Materials Research
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• v.9 no.3
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• pp.322-326
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• 1999

In this study, cold-rolling and appropriate annealing was adopted for the grain refining of Cu-26.65Zn-4. 05Al-0.31Ti(wt%) shape memory alloy. For the cold deformation of this alloy the ducti1e $\alpha$-phase must be contained. After heat treatment at $550^{\circ}C$ the $(\alpha+$\beta)$-dual phase with 40vol.% $\alpha$-phase was obtained which could be rolled at room temperature. This alloy was cold rolled into a final thickness of 1.0mm with total reduction degrees of 70% and 90%. The rolled sheets were betanized at $800^{\circ}C$ for various times, then quenched into ice water. The grain size of co]d rolled samples were $60~80\mu\textrm{m}$ which is much smaller comparing with the hot-rolled samples. And the 90% rolled sample showed smaller grain size than the case of the 70% rolled one. The small grain size had influence on the phase transformation temperatures and stabilization of the austenitic phases.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.142-146
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• 2001

In this study, it was investigated the influence of cold rolling factors on the edge drop. Edge drop was highly affected by the shape of work roll, the amount of work roll shift and the crown of hot strip, but the effect of bending force at the front stand was relatively small. The used numerical model was examined by comparing to the result of measured field data, and it showed a qualitative agreement with each other.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.220-223
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• 2001

Until now, the clamp yoke of automobile has been largely manufactured by hot forging or burring process. Through the study, the precision cold forging process for clamp yoke has been analysed by using rigid-plastic finite element analysis code, DEFORM-3D. It has shown various results of the FEM simulation. An engineer should select the proper process considering the amount of product.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.512-517
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• 1993

The cold rolled strip meets continuously rising demands on the less deviation of thickness at the width direction of their rolled products. Especially, the special interest has been to find the methods to reduce the edge drop which influences seriously on the yield losses and the quality of the rolled products. In this study, the influence of hot coils on the thickness profile of cold rolled strip was analyzed. For obtainint the tapered work roll shig\ft conditions, the thermal crown and the flattening between the work roll and the strip were calculated, and the main parameters which have mostly effects on the edge drop were simulated. Also the obtained conditions from the simulation were applied to Tandem Cold Rolling Mill to investigate the change of the edge drop and the crown ratio depending on the amount of work roll taper and the length of contact of taper. The results of the application led to better thickness profile than conventional one.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.242-247
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• 2009

The present study has been conducted to reduce the cold air drying rate. According to the cold air drying method, the quality-excellent product could be made and there would be little change of color, taste and smell. As compared with the hot air drying, the cold air drying equipment has the superior dehumidification in a constant drying zone. However, in a falling drying zone that equipment is not energy-efficient because the drying period could be longer by the dehumidificated.

• Transactions of Materials Processing
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• v.18 no.5
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• pp.377-384
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• 2009

The shape of edge cracking in rolling process generally occurred "V" shape. This cracking is successively generated at width edge of strip. The edge cracking is developed to center of strip during rolling process. In the results, the strip is occurred fracture, and the productivity is gone down because of the extensive production time. Accordingly, we need to control crack propagation during rolling process. But, the control of cracking is very difficult in rolling process. Previously the studies of edge cracking were mainly performed on hot rolling process. In this paper, the shape of the edge cracking in rolling was estimated according to process conditions such as initial edge crack size, reduction ratio and tension using FE-simulation and the simplicity experiments on cold rolling process.

• The Korean Journal of Nuclear Medicine
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• v.34 no.6
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• pp.516-520
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• 2000

Acute osteomyelitis is usually shown as a localized area of increased activity (hot uptake) in the infectious focus on bone scintigraphy. In our patient, absence of radioactivity (cold lesion) was noted in the distal metaphyseal and diaphyseal regions of his right femur. Initial x-ray was interpreted as normal except for mild soft tissue swelling in the right thigh. The lesion was confirmed as an acute osteomyelitis with subperiosteal abscess on surgery. Staphylococcus aureus was the etiologic organism. We describe a case of acute osteomyelitis in a one-year-old boy shown as a cold lesion on bone scan.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.8
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• pp.667-673
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• 2001

As an alternative cooling method to reduce environmental hazard, vortex tubes have been studied for energy separation into cold and hot streams. Hence, the experiments were carried out systematically to find the best ratio of vortex chamber diameter to tube diameter. Also, the work was don to investigate how inlet pressure and geometric ratios of vortex tube affected temperature differences at tow needs as ell as cooling capacity and cooling efficiency. The result showed that the maximum temperature differences at the both ends and the maximum cooling efficiency were obtained when the ratio of vortex chamber diameter was about 1.45, while the inlet pressure ws not higher than 0.7 MPa.

• Steel and Composite Structures
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• v.30 no.5
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• pp.457-469
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• 2019

Steel pallet racking industry has globally used from the industrial revolution and has deeply evolved from hot-rolled profile into cold-formed profile to raise the optimization in engineering field. Nowadays, some studies regarding cold-formed steel profile have been performed, but fewer studies in terms of cold-formed pallet racking specifically in connection due to the semi-rigid behavior by lug-hooked into the upright have been conducted. The objective of this study is to review the related literature on steel storage racking connection behavior.