• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2003.05a
• /
• pp.249-253
• /
• 2003

In recent years, developments of light weight vehicle are one of the most important issues in automotive makers. New materials and new processes have been studied on the point of weight saving of chassis worldwide. Associated with materials, applications of high strength steel, aluminium, magnesium are being developed. On the point of new processes, tailored welded blank and hydroforming have been applied. In this paper, focusing to both material and process, we have applied hydroforming process to the engine cradle. In addition to that, three kinds of high strength steel have been applied to the development of light weight material for hydroforming. All the studies have been carried by FEM.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2014.05a
• /
• pp.218-219
• /
• 2014

The purpose of this study is to develop eco-friendly internal material of acrylic emulsion mortars using light-weight aggregate carrier which contains pyroligneous liquid. Four types of light-weight aggregates (vermiculite, perlite, charcoal, zeolite) that are widely used in building materials are selected and the properties such as adhesion, water absorption coefficient, antibiosis, crack and impact resistance are evaluated in accordance with KS F 4715. As a result, the properties of acrylic emulsion mortars using light-weight aggregate carrier are satisfied with KS requirements. The antibiosis is improved with increasing zeolite light-weight carrier content.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.17 no.6
• /
• pp.130-135
• /
• 2018

Currently the automobile market is developing eco-friendly vehicles in order to cope with fuel efficiency regulations. Many studies have been conducted to improve travel performance and fuel economy of the environment-friendly vehicles, and vehicle manufacturers study how to manufacture light-weight vehicles for improving fuel economy for both existing vehicles and environment-friendly vehicles. Exemplary light-weight vehicle technologies include optimal design of vehicle body structure which is a light-weight vehicle method by changing component shapes or layout to optimize the vehicle body structure and the new process technology for using new light-weight and very strong materials Various studies.

• Journal of Korean Society of Steel Construction
• /
• v.17 no.1 s.74
• /
• pp.33-43
• /
• 2005

This paper presents the test results and evaluations for the energy dissipation capacity and compressive performance of light-weight hybrid panels. A total of 26 full-scale specimens of light-weight hybrid panels were tested. The parameters include the presence of light-weight foamed mortar, the specific gravity of light-weight foamed mortar (0.6, 0.8, 1.0, 1.2), the finishing materials (light-weight foamed mortar, OSB [Oriented Strand Board], gypsum board), the shape of bracing (x, ~), and the size of panels (1P-900 mm 2,400 mm, 2P-1,800 mm 2,400 mm). The results of the cyclic tests are somewhat different from those of monotonic tests, due to the different specific gravity of light-weight foamed mortar. It was found from the compressive tests that the ultimate strength and initial stiffness are increased by means of light-weight foamed mortar (2~2.5 times in ultimate strength and 2~3 times in initial stiffness).

• Journal of Korean Society of Steel Construction
• /
• v.19 no.5
• /
• pp.455-462
• /
• 2007

The purpose of this paper is to evaluate experimentally the compressive performance of horizontal joints for light-weight hybrid panel in-filled with light-weight foamed mortar. The parameters include the presence of light-weight foamed mortar, the specific gravity of light-weight foamed mortar (0.8, 1.2), the finishing materials (light-weight foamed mortar, Oriented Strand Board [OSB], gypsum board), and the fixed shape of the hybrid panel. As the improved details for fixed end, the peak strength and the stiffness of the light-weight hybrid panel are enhanced as follows: 1.07-2.7 times in peak load, 15-24 times in initial stiffness. The peak strength of the light-weight hybrid panel obtained by the test result is in agreement with the calculations, which is the criterion value according to the domestic code.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2023.11a
• /
• pp.137-138
• /
• 2023

The floating floor is a structure which introduced to reduce the noise of apartment houses. This structure can decrease vibration energy through resilient materials. However, it is limited to completely construct resilient materials in South Korea due to floor heating structure and other reasons. And It is a controversial issue how well the resilient materials should be constructed to prevent floor impact noise. These resilient defect areas are typically found in wall corners, door sills, hot water dispenser in kitchen and areas where thermal insulation is attached. This study investigates the acoustical effect of the defect areas in two ways. First, it is analyzed by several assumption conditions and calculated how much deviation would occur. Then we researched the deviation of the 76 field test data about light-weight floor impact noise. This study could be useful for a constructor to determine how much should minimize resilient materials defect areas.

• Macromolecular Research
• /
• v.15 no.3
• /
• pp.216-220
• /
• 2007

A new polyfluorene-based copolymer having 2-ethylhexyloxy-5-methoxy-l,4-phenylene as an electron donating group and 2,5-diphenyl-oxadiazole as an electron withdrawing group was synthesized by the Suzuki coupling reaction. The obtained copolymer was characterized by $^1H-NMR,\;^{13}C-NMR$, and IR-spectroscopy. The weight average molecular weight ($M_w$) of the obtained polymer was 18,600 with a polydispersity index of 1.5. The maximum photoluminescence of the solution and film of the polymer was observed at 453 nm and 456 nm, respectively. A double-layer device with the configuration, ITO/PEDOT/copolymer/Al, emitted blue light at 460 nm.

• Journal of the Korean Society for Precision Engineering
• /
• v.28 no.11
• /
• pp.1297-1308
• /
• 2011

The light-weight design of UTM (Urban Transit Maglev)-02 car-body frames are performed, based on initial configuration. The thicknesses of fourteen sub-structures are defined as design variables and the loading condition is considered according to weight of sub-structures, electronic and pneumatic modules and passengers. For efficient and robust process of design optimization, objective function and constraints are approximated by response surface approximation. Structural analysis is performed at some sampling points to construct the approximated objective function and constraints composed of design variables. Design space is changed to find many optimal candidates and best optimal design can be found eventually. The Matlab Optimization Toolbox is used to find optimal value and sensitivity analysis about each design variable is also performed.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2016.10a
• /
• pp.119-120
• /
• 2016

This study is about development of inorganic insulation material using by-product materials. The organic material is due to toxic gas emission, when a fire occurs. And it has lower water resistance. The inorganic material is heavy and worse thermal performance than organic materials. In this study, installed light weight ceramic insulation by concrete structure to evaluation fire resistance.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2014.05a
• /
• pp.214-215
• /
• 2014

Technologies on energy saving and materials used in curtain walls have progressed with increase of high-rise and large buildings. This study is explain fire resistance performance of the curtain walls. And focused on bond strength of light-weight inorganic ceramic board in high temperature for fire resistant curtain-wall system. From the result, curtain-wall system high fire resistant using the light-weight inorganic ceramic board.