Abstract: Provided are an apparatus, a memory device, and a method for multi-phase clock training. The memory device includes a clock training circuit configured to receive a clock through a first signal pin, among a plurality of signal pins and connected to a first signal line connected to the first signal pin. The clock training circuit generates a multi-phase clock upon receiving the clock, and generates a three-dimensional (3-D) duty offset code (DOC) for the multi-phase clock by simultaneously phase-sweeping between three internal clock signals in a duty adjustment step in the multi-phase clock. The memory device corrects a duty error of the multi-phase clock using the 3-D DOC.

Abstract: A structural member with a core bar which reduces manufacturing costs, enables easy construction of various curved building structures such as a dome-shaped building structure or an arch-shaped building structure without a truss structure or a formwork. The structural member includes: at least one elastic core bar formed in a bar shape; and an outer body or an outer cover into which the at least one core bar is inserted. The core bar is formed at least one of wood such as a bamboo strip or a composite bamboo bar, a synthetic resin material, a glass fiber composite material, and a carbon fiber composite material. The outer body or the outer cover is formed of at least one of a metallic material such as aluminum, a synthetic resin material, a glass fiber composite material, and a carbon fiber composite material.