The sliding motion of the piston ring inside the cylinder wall causes friction losses for the engine. The friction caused by piston rings is approximately 24% of the total mechanical friction losses for the engine. The design of the piston rings is therefore a compromise between minimising friction while achieving good sealing and an acceptable lifespan.

Lubrication of piston rings is difficult and has been a driving force to improvements in the quality of motor oil. The oil must survive high temperatures and harsh conditions with a high-speed sliding contact. Lubrication is particularly difficult as the rings have an oscillating motion rather than continuous rotation (such as in a bearing journal). At the limits of piston movement, the ring stops and reverses direction. This disrupts the normal oil wedge effect of a hydrodynamic bearing, reducing the effectiveness of the lubrication.

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In this paper we analyzed the electromagnetic behavior of high superconductor under the quench state using finite element method. Poisson equation was used in finite element analysis as a governing equation and was solved using algebra equation using Gallerkin method. We first investigate d the electromagnetic behavior of U-type superconductor. Finally we applied our analysis techniques to 5.5 kVA meander-line superconducting fault current limiters (SFCL) which are currently developed by many power-system researcher in the world. Meshes of 14,600 elements were used in analysis of this SFCL. Analysis results show that the distribution of current density was concentrated to inner curvature in meander-line type-superconductors and maximum current density 14.61$ A/\m^ 2$ and also maximum Joule heat was 6,420 W/㎥. We concluded that this meander line-type SFCL was not pertinet fur uniform electromagnetic field distribution.

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This study aims to find the determinants which affects the consumption of art and culture. With this goals, we conducted the empirical analysis of the 2012 Survey Reports on Cultural Enjoyment. The results are summarized as follows: First, while the 30 percent of respondents have not experienced the enjoyment of art and culture, the rest have enjoyed one kind of cultural events such as movie. Second, there are significant differences of art and culture consumption depending on cultural capital, economic capital, demographic characteristics and area. Third, the results of multiple regression show that Model 1 (all type) and Model 2 (high-culture performing arts) are affected by cultural capital, economic capital and demographic characteristics except area. However, all of these factors have contributed to Model 3 (middlebrow cultural activities). This implies that increasing the consumption of art and culture is a key in expanding culture education for all ages and culture public service especially for the elderly