Abstract: A power conversion apparatus may include a main converter including a main housing and at least one transformer disposed in an interior of the main housing, a sub-converter including a sub-housing coupled to an upper portion of the main housing and a voltage boost assembly disposed in an interior of the sub-housing, a lower cooling unit provided in a lower portion of the main housing to support the at least one transformer, and an upper cooling unit provided in a lower portion of the sub-housing to support the voltage boost assembly.

Abstract: A fuel cell apparatus of the disclosure includes a case having defined therein a first accommodation space and a second accommodation space, which are isolated from each other by a partition wall, a first cover covering the first accommodation space in the case, a second cover covering the second accommodation space in the case, a power distribution unit disposed in the first accommodation space, and a power conversion unit disposed in the second accommodation space.

Abstract: A fuel cell vehicle includes a cell stack, a DC level converter, an output unit, a first switching unit disposed between a positive output terminal of the DC level converter and a positive input terminal of the output unit, a second switching unit disposed between a negative output terminal of the DC level converter and a negative input terminal of the output unit, a resistor and a third switching unit connected to each other in series between the positive output terminal of the DC level converter and the negative output terminal of the DC level converter, a fourth switching unit disposed between a contact point between the resistor and the third switching unit and the positive input terminal of the output unit, and a controller for controlling switching operation of the first, second, third and fourth switching units according to an operation mode.

Abstract: An electrochromic display device (ECD) for an optical pick-up apparatus which is capable of maximizing a transmissivity of a laser beam by forming a reflection prevention layer on the outer surfaces of transparent substrates, includes first and second transparent substrates formed at both sides of the ECD with a predetermined interval therebetween, first and second transparent electrodes coated on the inner surfaces of the transparent substrates, respectively, an electrochromic layer coated on the inner surface of the second transparent electrode so that colorizing or decolorizing may be carried out reversibly, a counter eletrode layer coated on the inner surface of the first transparent electrode, an electrolytic layer formed between the counter electrode layer and the electrochromic layer, and a reflection prevention layer coated to have more than one layer so as to prevent a beam from being reflected on the outer surfaces of the first and second transparent substrates.