Abstract: The present invention relates to a plated steel sheet having excellent corrosion resistance, workability and surface quality, and at the same time, capable of reducing occurrence of liquid metal embrittlement (LME).

Abstract: One aspect of the present invention provides a plated steel sheet and a manufacturing method therefor, the plated steel sheet comprising: a base steel sheet; a Zn—Mg—Al-based plated layer provided on at least one surface of the base steel sheet; and an Fe—Al-based inhibition layer provided between the base steel sheet and the Zn—Mg—Al-based plated layer, wherein, on the surface of the Zn—Mg—Al-based plated layer, the total area fraction of an Al single phase and MgZn2 phase is 45-60%, and the area ratio of the MgZn2 phase to the Al single phase is 1.2-3.3.

Abstract: Provided are a plated steel sheet and a method for manufacturing same, the plated steel sheet comprising: a base steel sheet; a Zn—Mg—Al based steel sheet plating layer provided on at least one surface of the base steel sheet; and an Fe—Al based inhibition layer provided between the base steel sheet and the Zn—Mg—Al based plating layer, wherein the plating layer comprises, in wt %: 4% or more of Mg; 2.1 times or more of Mg content and 14.2% or less of Al; 0.2% or less (including 0%) of Si; 0.1% or less (including 0%) of Sn; the remainder Zn; and unavoidable impurities.

Abstract: A voltage measurement device is provided. The voltage measurement device includes a contact portion configured to contact an electric wire for transmitting an alternating current (AC) voltage and to output an induced voltage induced by the AC voltage in a surface of the electric wire, a capacitive element connected in series to the contact portion, and a controller configured to calculate amplitude of the AC voltage using the induced voltage output from the contact portion and a second voltage output from the capacitive element.

Abstract: A voltage measurement device is provided. The voltage measurement device includes a contact portion configured to contact an electric wire for transmitting an alternating current (AC) voltage and to output an induced voltage induced by the AC voltage in a surface of the electric wire, a capacitive element connected in series to the contact portion, and a controller configured to calculate amplitude of the AC voltage using the induced voltage output from the contact portion and a second voltage output from the capacitive element.

Abstract: The present invention relates to an upstream ozone contact tank for removing residual ozone. The upstream ozone contact tank includes an inlet through which purified raw water flows, at least one contact chamber, at least one reaction chamber, an upstream contact chamber, and an outlet that discharges ozone-treated raw water. Especially, the invention provides an upstream contact chamber between the reaction chamber and outlet, wherein the upstream contact chamber includes carbonaceous filter media mounted on a porous plate. An openable gate unit is installed at the lower part of a panel partitioning a final reaction chamber and the upstream contact chamber and controls flow rate. Additionally, the invention enables upstream flow of the raw water flowing into the upstream contact chamber from the final reaction chamber so that the raw water may pass through the carbonaceous filter media upwardly.

Abstract: The present invention relates to an upstream ozone contact tank for removing residual ozone. The upstream ozone contact tank comprises an inlet through which purified raw water flows, at least one contact chamber, at least one reaction chamber, an upstream contact chamber, and an outlet that discharges ozone-treated raw water. Especially, the invention provides an upstream contact chamber between the reaction chamber and outlet, wherein the upstream contact chamber includes carbonaceous filter media mounted on a porous plate. An openable gate unit is installed at the lower part of a panel partitioning a final reaction chamber and the upstream contact chamber and controls flow rate. Additionally, the invention enables upstream flow of the raw water flowing into the upstream contact chamber from the final reaction chamber so that the raw water may pass through the carbonaceous filter media upwardly.