• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.22 no.1
• /
• pp.1-6
• /
• 2016

How do we use onggi, Korean earthenware, for container of dough during fermentation instead of stainless steel container? How does it affect the flavor of bread if onggi tray is used in baking instead of steel tray? We tried to confirm those. As a result, the characteristics of onggi made positive effect on dough in fermenting room. The time, when the temperature of the center in the dough is equilibrated to that of surface on the dough, take shorter in onggi than in stainless steel. It could make the temperature of dough maintained evenly with little deviation, which could result in shorter fermentation time. Volume and surface color of the bread baked on onggi tray were better than on steel tray. The bread baked on onggi tray got higher score on overall acceptability in sensory test than on steel tray. Therefore, if onggi is used during baking, it could produce better quality of bread like making positive effect on fermented foods.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2012.05a
• /
• pp.331-332
• /
• 2012

Structural steel has been used as a primary materials to columns and beams since 1960's in Korea with an advantages of excellent of load-bearing capacity and design flexibility, and faster construction. However, if the steel columns made of structural steel exposed to fire the load-bearing capacity is going down steadily and finally reach to collapse. Therefore, building regulation requires fire resistance according to building occupation, scales. The fire resistance can be evaluated two categories. One is prescriptive method that is based on building regulation, specification and so on and the other is performance-based fire engineering method. The latter can be designed based on scientific and engineering consequences. The easiest evaluation way using the fire engineering design is comparing to the limiting temperature and maximum temperature calculated based on heat transfer theory. If the limiting temperature of a column exceeds the maximum temperature of it, the column can carry the load during the fire. Therefore, the database of limiting temperature is very essential for evaluation of column. In this paper, to build the database of column made of rectangular hollow sections 8 fire tests with loading were conducted and the relation between the limiting temperature and the applied loads showed in reverse proportion.

• Steel and Composite Structures
• /
• v.21 no.2
• /
• pp.267-287
• /
• 2016

The seismic performance of the ordinary steel reinforced concrete (SRC) columns has no significant improvement compared to the reinforced concrete (RC) columns mainly because I, H or core cross-shaped steel cannot provide sufficient confinement for core concrete. Two improved SRC columns by constructing with new-type shaped steel were put forward on this background, and they were named as enlarging cross-shaped steel and diagonal cross-shaped steel for short. The seismic behavior and carrying capacity of new-type SRC columns have been researched theoretically and experimentally, while the shear behavior remains unclear when the new-type columns are joined onto SRC beams. This paper presents an experimental study to investigate the shear capacity of new-type SRC joints. For this purpose, four new-type and one ordinary SRC joints under low reversed cyclic loading were tested, and the failure patterns, load-displacement hysteretic curves, joint shear deformation and steel strain were also observed. The ultimate shear force of joint specimens was calculated according to the beam-end counterforce, and effects of steel shape, load angel and structural measures on shear capacity of joints were analyzed. The test results indicate that: (1) the new-type SRC joints display shear failure pattern and has higher shear capacity than the ordinary one; (2) the oblique specimens have good bearing capacity if designed reasonably; and (3) the two proposed construction measures have little effect on the shear capacity of SRC joints embedded with diagonal cross-shaped steel. Based on the mechanism observed from the test, the formulas for calculating ultimate shear capacity considering the main factors (steel web, stirrup and axial compression ratio) were derived, and the calculated results agreed well with the experimental and simulated data.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.815-820
• /
• 2011

The railway bridge of the domestic still has been used steel base such as sperical bearing and pot bearing widely. However, the bearing of steel series is occured corrosion frequently, reduced durability and raised maintenance cost excessively due to the nature of the material. If the elastomeric bearing which is widely used in highway bridge is applied to the railway bridge, it will be able to compensate this defect a lot. In order to apply to the railway bridge used for highway bridge, is needed the control of the bridge ends deflection, lateral displacement and negative reaction. Therefore, the elastomeric bearing can be applied to the railway bridge enough, if installed negative reaction key for control of the bridge ends deflection, improved shear wedge performance for control of the lateral force, adjust the thickness of the elastomeric pad for the minimize deflection, in addition, can be economic design of sub-structures due to damping effect.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2003.10a
• /
• pp.179-182
• /
• 2003

Equal channel angular pressing (ECAP) provides an efficient procedure for introducing an ultrafine grain size into a material. In this study, ECAP were conducted on IF-steel to investigate the effect of friction and processing temperatures on the deformation characteristics of the samples. Due to the blocking effect of the previously pressed samples residing in the exit channel, the shear pattern (especially on the bottom region) changes.

• Transactions of Materials Processing
• /
• v.16 no.5 s.95
• /
• pp.406-411
• /
• 2007

The microstructure and the hardness of interstitial free steel processed by equal channel angular pressing (ECAP) was investigated experimentally. ECAP processing of route A and route C was compared with regard to grain refinement by transmission electron micrographs. Micro hardness evolution was correlated with the gram structure produced by ECAP. Especially, the effects of the ECAP processing temperature and the number of processing passes were discussed in terms of grain refinement.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 1999.08a
• /
• pp.349-355
• /
• 1999

The texture inhomogeniety during rolling is one of the greatest problems. Especially, shear texture develops more easily during ferritic rolling of steel sheets at high temperatures due to friction between rolls and the material. In this study, the influence of front and back tensions on the texture development during ferritic rolling has been studied. The rolling textures were simulated using the full constrains Taylor-Bishiop-Hill model with the strain history obtained from finite element analysis. The calculated textures showed that the back tension rolling could reduce the shear component more effectively than front tension or rolling without tension. However, the experimental results showed that the lension effect was very small compared to our prediction. It might be attributed to initial texture and difference in frictions between simulation and experiments.

• Journal of the Korean institute of surface engineering
• /
• v.32 no.4
• /
• pp.555-560
• /
• 1999

Gas wiping of continuously hot-dip galvanized coating on steel strip has generated edge overcoating and noise problems. The overcoating of zinc in the edge zone from edge to 50mm inside of the strip along its width was measured and analyzed. The overcoating is thought to occur due to the reduced impinging pressure of wiping gas onto the strip edges by the boundary effect and it can decrease by 50% or more by applying edge baffles when the baffle-to-strip distance is maintained to 20mm or less. The overcoating was compared with edgedrop of the cold-rolled steel substrate. Edge buildup mostly at the edge area 10 to be 20mm from the edge results in if the edgedrop is not sufficient enough to compensate for the overcoating to be flat on the edgedrop or/and if the overcoating is not small enough to the given edgedrop. Edge baffles can reduce effectively this type of edge buildup.

• International journal of steel structures
• /
• v.18 no.4
• /
• pp.1373-1383
• /
• 2018

Experimental study was conducted to investigate the seismic behavior of roof joint. Eight full-scale specimens were tested considering the effects of axial force, joint height, hole shape of base plate and edge distance of concrete on the failure mode and resistance capacity of roof joint. With the increase of axial force, the hysteretic curves were fuller. The mechanical model of roof joint change from bending to shear. With the increase of joint height, the ultimate strength of roof joint decreased. If the hole shape of base plate changed from circle to loose, the slip behavior of roof joint appeared and the ultimate strength of roof joint decreased. The damage of edge concrete may occur if the edge distance of concrete was not big enough.

• Transactions of Materials Processing
• /
• v.7 no.5
• /
• pp.445-449
• /
• 1998

In order to obtain optimum process variables during the drawing of stainless steel sheets rectangular cup drawing tests were carried out with several technically available stainless steel sheets. As parameters on testing materials for die and punches lubrication and blank holding forces were selected. Testing parameters played an important role if the deformed material was thin. Effect of material properties on the deformation behaviors was also discussed by using testing parameters selected in this experiment. From the test results we suggest the appropriate conditions to be applicable to the actual manufacturing processes