Abstract: An IC card has a card information memory area wherein there are written a master public key nA, card secret keys pU and qU, a card public key nU, a card identification number IDU, and a first master digital signature SA1 for information including the card identification number. An IC card terminal has terminal information memory area wherein there are written a master public key nA, terminal secret keys pT and qT, a terminal public key nT, a terminal identification number IDT, and a second master digital signature SA2 for information including the terminal identification number IDT. When inserted into the IC card terminal, the IC card sends thereto the data nU, IDU, and SA1. The IC card terminal verifies the digital signature SA1 by the master public key nA and, if it is valid, transmits the data nT, IDT and SA2 to the IC card.

Abstract: An IC card has a card information memory area wherein there are written a master public key nA, card secret keys pU and qU, a card public key nU, a card identification number IDU, and a first master digital signature SA1 for information including the card identification number. An IC card terminal has terminal information memory area wherein there are written a master public key nA, terminal secret keys pT and qT, a terminal public key nT, a terminal identification number IDT, and a second master digital signature SA2 for information including the terminal identification number IDT. When inserted into the IC card terminal, the IC card sends thereto the data nU, IDU, and SA1. The IC card terminal verifies the digital signature SA1 by the master public key nA and, if it is valid, transmits the data nT, IDT and SA2 to the IC card.

Abstract: An IC card has a card information memory area wherein there are written a master public key nA, card secret keys pU and qU, a card public key nU, a card identification number IDU, and a first master digital signature SA1 for information including the card identification number. An IC card terminal has terminal information memory area wherein there are written a master public key nA, terminal secret keys pT and qT, a terminal public key nT, a terminal identification number IDT, and a second master digital signature SA2 for information including the terminal identification number IDT. When inserted into the IC card terminal, the IC card sends thereto the data nU, IDU, and SA1. The IC card terminal verifies the digital signature SA1 by the master public key nA and, if it is valid, transmits the data nT, IDT and SA2 to the IC card.

Abstract: A magnetic recording powder for use as a material for magnetic recording media including magnetic tapes and magnetic cards, the powder having a high coercive force at room temperatures and a low Curie point, consists of at least one element selected from the group consisting of Y and rare-earth elements (R): 5-20 atomic %, B: 5-20 atomic %, Mn: 4-20 atomic %; and Fe and inevitable impurities: the balance. If required, the powder may further contain Al: 1-10 atomic %, and/or Cr: 1-10 atomic %. The powder has a mean particle size of 0.5-2 .mu.m and a mean crystal grain size of 0.1-0.4 .mu.m.

Abstract: A dual layered magnetic card with an apparatus for reading data therefrom and recording data thereon. The magnetic card includes (a) a card body, (b) a first magnetic layer disposed on the card body, the first magnetic layer including a first magnetic material, (c) a second magnetic layer disposed on the first magnetic layer, the second magnetic layer including a second magnetic material having Curie temperature lower than that of the first magnetic material and a coercive force at an ambient temperature higher than that of the first magnetic material. Also disclosed is an apparatus for reading data on the magnetic card, having a reader, post processor and data eraser, and an apparatus for reading and recording data having a recorder, reader, post processor and a data eraser.

Abstract: In the subject magnetic card, first magnetic recording layer 2 is laid over substrate 1. First magnetic recording layer 2 has a coercive force that enables magnetic recording of data. Second magnetic recording layer 4, having a coercive force smaller than that of first magnetic recording layer 2, is laid over first magnetic recording layer 2, with shielding intermediate layer 3 interposed therebetween. Magnetic shielding layer 5 is provided as an uppermost magnetic layer.

Abstract: A multicontact sealed electromagnetic coordinate selection device comprises a movable contact type spring supported at both ends by supporters at a prescribed interval from a metal plate and electrically insulated from said metal plate, the movable contact type spring elastically supporting a plurality of movable contacts facing the corresponding stationary contacts formed on the upper ends of stationary contact terminals which penetrate said metal plate. The lower ends of said stationary contact terminals are supported by a magnetic metal member.

Abstract: An electromagnetic coordinate selection device comprising a plurality of electromagnetically operated cross point switches arranged in a matrix form and a plurality of magnetic cores disposed at points corresponding to said cross point switches for operation thereof, with any desired cross point switch closed only when the first and second coils wound about the magnetic cores are additively excited wherein the magnetic cores are each of the composite type to stabilize the operation of the cross point switches and the cross point switches are collectively sealed in a single container or in groups in a plurality of vessels provided in a number equal to or smaller than the number of the conductors arranged in the direction of the row or column of said matrix.