Abstract: A storage system includes a storage controller and a plurality of storage drives. The storage controller holds power management information for managing power supplied to the storage system and power consumption of an operating mounted device of the storage system, and definition information for defining a relationship between power states and power consumption of the plurality of storage drives. The storage controller determines a power budget that can be supplied to the plurality of storage drives, based on the power management information according to a change in a configuration of the storage system, and determines a power state of each of the plurality of storage drives based on the power budget and the definition information.

Abstract: A tin, lead, or tin-lead alloy plating bath comprising, as essential ingredients, an alkali metal salt, and a soluble divalent tin compound or/and a lead compound, all of an aliphatic or aromatic sulfocarboxylic acid of the general formula ##STR1## wherein R is a C.sub.1-4 hydrocarbon radical, M.sub.1 is a hydrogen atom or alkali metal atom, M.sub.2 is an alkali metal atom, and X.sub.1 and X.sub.2 are each a hydrogen atom, OH, COON, or SO.sub.3 N (where N represents a hydrogen atom or alkali metal atom).

Abstract: A tin-lead alloy plating bath based on a principal plating bath comprising an alkanesulfonic or alkanolsulfonic acid and both bivalent tin and lead salts thereof is characterized by the addition of a guanamine compound having the general formula ##STR1## wherein R.sub.1 and R.sub.2, which may be the same or different, represent each a hydrogen atom, C.sub.1-18 straight- or branched-chain alkyl radical, C.sub.1-18 straight- or branched-chain alkoxy-lower alkyl radical, or a C.sub.3-7 cycloalkyl radical, or R.sub.1 and R.sub.2 may combine to form a carbon cycle or hetero cycle, and A represents a lower alkylene radical.

Abstract: A tin, lead or tin-lead alloy plating bath, which comprises(A) a principal plating bath containing an alkanesulfonic or alkanolsulfonic acid, and either a divalent tin salt or a divalent lead salt thereof or both;(B) at least one of surfactants comprising(a) a cationic surfactant selected from the group consisting of quarternary ammonium salts, alkyl pyridinium salts, alkyl imidazolinium salts and higher alkyl amine salts,(b) an amphoteric surfactant selected from betaines, or(c) a nonionic surfactant selected from the group consisting of condensation products of ethylene oxide and/or propylene oxide with a styrenated phenol, a higher alcohol, an alkylphenol, an alkylnaphthol, a fatty acid amide, a sorbitan or a phosphate; and(C) at least one of levelling agents selected from the group consisting of alkylidene sulfamic acids, quinolinol derivatives, benzotriazole derivatives, dialkylidene o-phenylene diamines, benzaldehyde derivatives, triazine derivatives, salicylic acid derivatives and nitriles.