Abstract: The present invention relates to a concentration indicator of a metal component contained in a plating solution and a plating method using the same and, more specifically, as the concentration of a plating metal component to be plated is lowered, the color of the plating solution is changed to visually indicate a change in concentration, and thus a worker can readily manage the concentration of a metal component contained in a plating solution within a short time. In addition, whether a plating metal component should be replenished can be determined in real-time so as to enable the precision and reliance of plating work to be improved, workability is improved by continuous maintenance, and cost is reduced.

Abstract: Disclosed is a storage device reader for interfacing a storage device and a user terminal, which includes a storage unit and a control unit. The data storage unit stores reader recognition information uniquely assigned to the storage device reader. The control unit retrieves reader recognition information stored in the storage device, determines whether or not the retrieved reader recognition information matches reader recognition information stored in the data storage unit, and transferring a file list stored in the storage device to the user terminal if the retrieved reader recognition information matches the stored reader recognition information.

Abstract: Disclosed is a portable storage device including a fingerprint sensor, a fingerprint data processing unit, a data repository, a data processing unit and the like. The fingerprint data processing unit outputs a fingerprint matching signal when fingerprint information received from the fingerprint sensor matches authentication fingerprint information of the fingerprint data repository. If the fingerprint matching signal is received from the fingerprint data processing unit, the data processing unit retrieves a data requested by the user terminal from the data repository, converts the retrieved data into a read-only data and transmits the read-only data to the user terminal.

Abstract: Disclosed is a portable storage device including a fingerprint sensor, a fingerprint data processing unit, a data repository, a data processing unit and the like. The fingerprint data processing unit outputs a fingerprint matching signal when fingerprint information received from the fingerprint sensor matches authentication fingerprint information of the fingerprint data repository. If the fingerprint matching signal is received from the fingerprint data processing unit, the data processing unit retrieves a data requested by the user terminal from the data repository, converts the retrieved data into a read-only data and transmits the read-only data to the user terminal.

Abstract: Disclosed is a storage device reader for interfacing a storage device and a user terminal, which includes a storage unit and a control unit. The data storage unit stores reader recognition information uniquely assigned to the storage device reader. The control unit retrieves reader recognition information stored in the storage device, determines whether or not the retrieved reader recognition information matches reader recognition information stored in the data storage unit, and transferring a file list stored in the storage device to the user terminal if the retrieved reader recognition information matches the stored reader recognition information.