Abstract: In a high frequency power amplifier module of a multi-stage structure in which a plurality of heterojunction bipolar transistors (npn-type HBTs) are cascade-connected, a protection circuit in which a plurality of pn junction diodes are connected in series is connected between the collector and emitter of each HBT. The p-side is connected to the collector side, and the n-side is connected to the emitter side. A protection circuit in which pn junction diodes of the number equal to or smaller than that of the pn junction diodes are connected in series is connected between the base and the emitter. The p-side is connected to the base side, and the n-side is connected to the emitter side. With the configuration, in the case where an overvoltage is applied across the collector and emitter due to a fluctuation in load on the antenna side, the collector terminal is clamped by an ON-state voltage of the protection circuits, so that the HBT can be prevented from being destroyed.

Abstract: A case capable of airtightly closing an opening of a mouth of a case body by screwing a lid on the case body; and rotating the lid smoothly in the circumferential direction when the lid is screwed on or unscrewed from the case body. The case including a case body having a mouth, and a lid detachably screwed on the mouth so as to close an opening of the mouth and connected to the case body via an opening and closing hinge so as to pivot in directions of opening and closing the mouth is provided with a rotary ring fitted and held around the mouth so as to rotate in a circumferential direction thereof and connected to the lid via the opening and closing hinge so that the lid rotates together with the rotary ring.

Abstract: When an active data copy process relative to a logical storage device is performed without involving a computer, an access permission/rejection of the computer to the logical storage device is checked by referring to a correspondence between WWN of the computer and a logical storage device identifier LUN to thereby determine whether an access to a copy source logical storage device and a copy destination logical storage device is permitted or not. It is therefore possible to prevent an outflow of illegal data from a storage subsystem to be caused by an active copy instruction command.

Abstract: A storage apparatus in a computer system, which includes a computer usage-status information reporting unit. When a computer makes an I/O request to the storage apparatus, the computer and a device for which I/O has been requested by the computer are identified, and the amount of data that has been transferred when I/O operations are performed, a cache hit ratio, and a processing time are measured. Then, the above information obtained and the above values measured are stored in the computer usage-status information in the storage apparatus. By using the computer usage-status information reporting unit, the stored computer usage-status information is referenced from the outside of the storage apparatus.

Abstract: The disk is connected to the server appliance via the network. The server appliance accessing the disk for storing the data is changed to change the server appliance processing the data. Here, the change of the server appliance for processing the data is simultaneously reflected to the setting of the service provided by the computer system.