• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 1999.08a
• /
• pp.452-456
• /
• 1999

Newly constructed plate shape control system, using attached shape measuring instruments and work roll bender, was put in service in No. 2 Plate Mill, POSCO. Recently, customers demand the improvement of flatness and plate crown accuracy. Many competition Plate Mill introducted shape control system, for example, pair cross mill, work roll bender which includes shape measuring instrument and shape control mathematical models, and No. 2 Plate Mill, POSCO introducted work roll bender and shape measuring instruments. This report describes the properties of No. 2 Plate Mill shape control system and work roll bender.

• Journal of the Korean Society of Safety
• /
• v.26 no.3
• /
• pp.34-42
• /
• 2011

Death disaster among the disasters in construction field is mainly occurred by crash, and the work plate is the main objects causing crash. This study was performed by interview with workers in construction field to evaluate the consciousness on safety and to analyze the type of use and the state. Finally the problems while using work plate were appeared with its requirements for the improved use. Based on the results from this study, amendments were proposed for some parts of regulation related, and further four types of development on the safe work plate were presented. It is expected that the safer construction environment could be composed by using the results.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1993.10a
• /
• pp.499-504
• /
• 1993

To find a way for establishing work roll initial crown according to roll conditions, computer simulation for predicting plate crown in plate mill is done and effects of roll conditions on plate crown is analysed. Roll gap profile and plate crown are measured to be compared to the calculated values. As a result,a regression equation to establish work roll initial crown according to roll cooditions such as backup roll diameter, backup roll crown and work roll crown is obtained.

• Journal of the Korean Society for Precision Engineering
• /
• v.12 no.3
• /
• pp.73-81
• /
• 1995

To find a way for establishing work roll initial crown according to roll conditions, computer simutation for predicting plate crown in plate mill is done and effects of roll conditions on plate crown is analyzed. Toll gap rorfile and plate crown are measured to be compared to the calculated values. As a result, regression equation to establish work roll initial crown according to roll conditions such as backup roll diameter, backup roll crown and work roll diameter is obtained.

• Journal of the Korean Society of Safety
• /
• v.26 no.3
• /
• pp.43-46
• /
• 2011

The work plate in a construction sites is a frequent cause of falling. But the bulk of the work plates lent to the construction site are handled carelessly by workers. There is general concern about performance declining by repetitive use. However, there is not a accurate guide, research and study on reuse work plate. This study was conducted in order to judge the classification guide to reuse work plate and measure the performance of classified reuse work plates. It is the result that even the A-grade plates classified to be in good shape by workers are below the performance standard. This means that the guide and classification are ineffective.

• Journal of the Korea Safety Management & Science
• /
• v.16 no.3
• /
• pp.55-62
• /
• 2014

During five years (Year 2009~2013), Total victims of 72 %(81,560 people) and those 50.6 %(1,258 people) of death accident occurs in small scale construction site which operate 2 million USD less construction budget. Especially, falling death accident account for 785 people, in the share of 33.2 %(261 people) death disaster takes due to defect of original cause materials. The major safety issues in small scale work place take place while scaffold installation, disassembling, work-plate improper installation or non-professional skills of workers. Furthermore, labor subcontract systems make small construction site shortage of resources. Those workers regard work-plate as unnecessary and consumables supplies. Because of that most of workers use unsafe workplace in most construction site. Therefore, in order to prevent falling accident occurring in small scale work site, government should organize related regulations such as "Work site safety construction method" and then expands education support, financial aid, and sourcing safety supplies for work plate which offer broad variety experiences. Also, introduce certificate solutions for various work plates to improve safety function such as anchoring type method and anti sliding function.

• East Asian mathematical journal
• /
• v.37 no.5
• /
• pp.619-626
• /
• 2021

In [1, 2], we studied the string-like system with time-varying delay. Unlike the string system, the plate system must consider both longitudinal and transverse strains. First, we consider the physical phenomenon of an axially moving plate concerning kinetic energy, potential energy, and work dones. By the energy conservation law in physics, we have a nonlinear plate-like system with internal time delay.

• International Journal of Aeronautical and Space Sciences
• /
• v.4 no.2
• /
• pp.79-87
• /
• 2003

Acoustic response control of a comer-pinned plate using piezoelectric wafers was studied, both theoretically and experimentally. Three different sizes of aluminum alloy plates were used and available ball joints were employed to hold the plate at the four comers. The plate with the largest aspect ratio showed the largest and most clear responses to the acoustic excitation in the range of frequencies (0~200Hz), and sound pressure levels (80~100dB) as predicted. The reduction of the acoustic response of the plate by piezoelectric actuator was very significant, more than expected, but abatement of the sound transmission through the plate was only slightly altered by the piezoelectric actuator. This work is an original work extending earlier work with doors excited by acoustic fields. The important difference is the used of ball joints to simulate the joints.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2004.05a
• /
• pp.421-428
• /
• 2004

Acoustic response control of a corner-pinned plate using piezoelectric wafers was studied, both theoretically and experimentally. Three different sizes of aluminum alloy plates were used and available ball joints were employed to hold the plate at the four corners. The plate with the largest aspect ratio showed the largest and most clear responses to the acoustic excitation in the range of frequencies (0～200Hz), and sound pressure levels (80～100dB) as predicted. The reduction of the acoustic response of the plate by piezoelectric actuator was very significant, more than expected, but abatement of the sound transmission through the plate was only slightly altered by the piezoelectric actuator. This work is an original work extending earlier work with doors excited by acoustic fields. The important difference is the used of ball joints to simulate the joints.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2004.11a
• /
• pp.633-636
• /
• 2004

Acoustic response control of a corner-pinned plate using piezoelectric wafers was studied, both theoretically and experimentally. Three different sizes of aluminum alloy plates were used and available ball joints were employed to hold the plate at the four comers. The plate with the largest aspect ratio showed the largest and most clear responses to the acoustic excitation in the range of frequencies $(0\sim200Hz)$, and sound pressure levels $(80\sim100dB)$ as predicted. The reduction of the acoustic response of the plate by piezoelectric actuator was very significant, more than expected, but abatement of the sound transmission through the plate was only slightly altered by the piezoelectric actuator. This work is an original work extending earlier work with doors excited by acoustic fields. The important difference is the used of ball joints to simulate the joints.