Abstract: The present disclosure relates to a brake disc including a braking part having a circular plate shape having a hollow portion and a plurality of coupling portions protruding and extending from an inner diameter surface thereof, and a hat part disposed in the hollow portion and having a plurality of insertion portions protruding laterally, in which the plurality of coupling portions is respectively coupled to the plurality of insertion portions, and the coupling portion of the braking part and the insertion portion of the hat part are joined to only one of an outboard portion or an inboard portion of the braking part. According to the present disclosure, it is possible to reduce noise occurring at a position at which the hat part and the braking part are coupled to each other and improve cooling performance.

Abstract: The present invention relates to a method of manufacturing soil reinforced by microbe-based bio-binders and soil produced by the method. The bio-binders are not harmful to humans, do not cause environmental pollution and secure sufficiently the soil strength and resistance against wind. According to the method, the soil is prepared by binding sand whose major components are silica and alumina, ureolytic microbes, urea, calcium ion, and polymer fibers, and the content of polymer fibers in sand ranges from 0.05 wt % to 5 wt %. In addition, it is preferable that the microbes provide CaCO3 at a rate at 1˜7×10?9 g CaCO3 ppt cell?1 hr?1 under optimum conditions.

Abstract: The present invention relates to a method of manufacturing soil reinforced by microbe-based bio-binders and soil produced by the method. The bio-binders are not harmful to humans, do not cause environmental pollution and secure sufficiently the soil strength and resistance against wind. According to the method, the soil is prepared by binding sand whose major components are silica and alumina, ureolytic microbes, urea, calcium ion, and polymer fibers, and the content of polymer fibers in sand ranges from 0.05 wt % to 5 wt %. In addition, it is preferable that the microbes provide CaCO3 at a rate at 1˜7×10?9 g CaCO3 ppt cell?1 hr?1 under optimum conditions.