• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 1997.10a
• /
• pp.32-39
• /
• 1997

The coiling station of ISP coil box is an equipment that winds a hot bar rolled at reduction unit into a coil without mandrel. In the coiling process, the roll gap of the bending unit is a significant one of several factors that influence bar coiling. To obtain a good bar-coil, the roll gap must be set appropriately according to the bar thickness. In this study, with 2-dimensional isothermal elastic-plastic finite element method, authors investigated influence of the change of the roll gap on the initial coiling shapes and the formed inner diameters of coils. Based on finite element analysis, authors proposed the appropriate roll gap according to the bar thickness to be able to wind a hot bar. The inner diameters of coils by results of analysis comparatively agreed with coling operation conducted in plant.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2000.10b
• /
• pp.873-878
• /
• 2000

Tension stiffening effects of reinforced concrete member with large diameter bar, mainly used at reactor building of nuclear power plant, are studied by uniaxial structural tests. Bond length and stress of steel bar, size of steel bar, and compressive strength of concrete are evaluated to tension stiffening by uniaxial tests. Problems and solution during the uniaxial test are suggested. The prevent splitting cracks, concrete cover-to-bar diameter ratio $c/d_{b}$ is kept 2.6~2.8. Because the bond length is increased as the size of steel bar, the specimen length of the D35 steel bar is required at least 2.0 m. The specimen length must be decided with bond length as well as concrete cover-to-bar diameter ratio to prevent splitting crack.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.16 no.5
• /
• pp.55-62
• /
• 2017

The grate bar, a component used in steel mills, is used in harsh environments where external disturbances such as high temperature, abrasion, corrosion, and impacts are present. Therefore, in this study, spray-coating was performed on the most severely affected surface to extend the lifetime of the grate bar. The thermal and mechanical properties of the sprayed coated bars were investigated based on the performances under abrasion, thermal shock, tension, and sand blasting, and the microstructures by microscope. By analyzing the thermal and mechanical properties of the uncoated original grate bar and coated grate bar and comparing them with one another, the physical performance improvement of the coated grate bar can be verified.

• Proceedings of the KSR Conference
• /
• 2002.05a
• /
• pp.503-508
• /
• 2002

In this study, the relation between the mtation which are usually caused by the creep of the contact wire, the bar geometry and the forces(wire tensions) for the triangle-shaped distribution bar and straight-shaped one in dependent tensioning device system is reviewed. According to the result a rotation of distribution bar in triangle-shaped one modifies the distribution of the tensions between the three wires hooked in a distribution bar. On the contrary, a rotation on the straight-shaped one leads to no tension distribution change. Therefore, to use the straight-shaped distribution bar instead of triangle-shaped one is recommended. In addition, the design contents of the distribution bar which will be used in electrification of Gyeongbu line are described in this paper.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.3 no.2
• /
• pp.159-164
• /
• 2015

This paper presents results on a study of the Rayleigh wave scattering in concrete with a steel bar using transient elastic waves. To study the characteristics of the scattered waves induced by a steel bar in concrete, a three-dimensional finite element method was adopted. A case for elastic wave propagation parallel to the steel bar is discussed. The effect of the cover thickness and steel bar diameter on the Rayleigh wave was studied. To confirm the numerical investigations, a concrete specimen containing a steel bar was made, and corresponding transient elastic wave experiments were conducted. It is believed that the result of this study can serve as an important reference in a nondestructive evaluation of concrete with a steel bar.

• Proceeding of EDISON Challenge
• /
• 2016.03a
• /
• pp.473-476
• /
• 2016

In this study, important design factors in Jansen leg mechanism by which two legs can be driven by only one input like a motor are considered through method of transmitting motion in three-bar linkage and Grashof law in four-bar linkage. In preliminary design, by using EDISON m-sketch and its simulation which can observe trace of feet, two identical four-bar linkages are initially designed and two three-bar linkages are added to four-bar linkages sequentially. By analyzing GL(Ground Length) and GAC(Ground Angle Coefficient), the adequacy of the preliminary design was estimated. Final design of walking apparatus is implemented using CAD software, Assembly2 of EDISON Designer. Finally, proposals to improve software used in this study are suggested.

• International conference on construction engineering and project management
• /
• 2005.10a
• /
• pp.1118-1123
• /
• 2005

This paper proposes the CPM bar chart (CBC), a hybrid of the bar chart and the critical path method (CPM). The CBC overcomes shortages of the fence bar chart, while still retaining its advantages. The fence with direction is applied instead of the broken fence, which triggers considerable problems to identify and apply in the fenced bar chart. In addition, the notorious task to find dummy activities is no longer required. Upon the benefits of simplicity in the bar chart and logical work sequence in the CPM network, the CBC provides a relatively easy way to create and understand a schedule, thus improving communication quality between project participants.

• Korean Journal of Optics and Photonics
• /
• v.34 no.2
• /
• pp.72-75
• /
• 2023

In this paper, a fiber-optic current sensor for a bus bar conductor based on the fiber Bragg grating (FBG) is proposed and demonstrated experimentally. The metal bus bar and a magnet are connected to each other through an FBG and the Bragg wavelength of the FBG is changed by magnetic force between the two connected devices. The experimental results showed that the Bragg wavelength of an FBG shifted by 650 pm as the 500 A direct current was applied to the bus bar.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2003.11a
• /
• pp.663-666
• /
• 2003

Using numerical analysis modeling of Multi-electrode Array that could be applied to the corrosion state measurement of a reinforcing steel bar in concrete, the steel bar location inside concrete can be probed by the investigation of the change of the measured impedance from concrete surface determined by the electrical impedance of interface between the steel bar and concrete, the electrical resistivity of concrete, the array of electrodes and the relative location and diameter of the steel bar.

• Proceedings of the Korea Contents Association Conference
• /
• 2010.05a
• /
• pp.520-523
• /
• 2010

I investigated the styles of progress bar in the top 8 China's websites. According to the authoritative literature, I calculated the time which each kind of operation needed. I investigated 400 examples which were used the progress bar. The statistical result confirmed my idea - progress bar's style and user's waiting time has the relations. Finally, I gave the revision comment which the progress bar's style improvement.