VERTICAL MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING DEVICE USING IT

    公开(公告)号:JPH09298114A

    公开(公告)日:1997-11-18

    申请号:JP646397

    申请日:1997-01-17

    Applicant: IBM JAPAN

    Abstract: PROBLEM TO BE SOLVED: To obtain a good vertical magnetic interaction as one of the characteristics of a vertical magnetic recording medium by a method wherein the composition of a vertical magnetizing film contains Co and Cr, the amount of the Cr is set in the extent of a specified atomic % of higher to a specified atomic % or lower and the vertical magnetizing film is magnetized in the vertical direction to the film surface of the magnetizing film. SOLUTION: A vertical magnetizing film 12 is formed on a glass substrate 10 as a recording layer via a base layer 11 consisting of a Ti layer. The composition of the film 12 contains Co and Cr, the amount of the Cr is contained more than 22 atomic % and is contained within the extent of 30 atomic % of lower and the film 12 is made to magnetize in the vertical direction to the film surface of the film 12. Thereby, a good vertical magnetic interaction can be obtained as one of the characteristics of a vertical magnetic recording medium and though the output of a magnetic recording device is reduced in the extent that the amount of the Cr is 22 atomic % or higher to 30 atomic % or lower, the device can obtain a good S/N ratio.

    SELLING MANAGING SYSTEM, SELLING MANAGING SERVER, SELLING SERVER, RESERVATION MANAGING SERVER, TERMINAL FOR ARTICLE PURCHASE, ARTICLE SELLING METHOD AND STORAGE MEDIUM

    公开(公告)号:JP2002056211A

    公开(公告)日:2002-02-20

    申请号:JP2000232305

    申请日:2000-07-31

    Applicant: IBM

    Abstract: PROBLEM TO BE SOLVED: To provide a system with which the seller to sell an article on a network buys the sold article back from a purchaser on prescribed conditions. SOLUTION: In a selling managing server provided with a ticket selling system 10 for accepting the purchase request of an article through a communication network and a ticket managing system 30 for managing selling of the article, the ticket selling system 10 accepts the purchase request and inquires whether a purchase applicant who issues this purchase request would agree with a buy-back request to the purchase applicant when there is the buy-back request to an article as a target of this purchase request. When the article as a target of the prescribed purchase request accepted by the ticket selling system 10 is already purchased by the purchase applicant who answers the agreement with this buy-back request, the ticket managing system 30 buys the relevant article back from this purchase applicant and provides the article to another purchase applicant who issues this prescribed purchase request.

    BATCH ERASURE-TYPE NONVOLATILE MEMORY

    公开(公告)号:JPH06274409A

    公开(公告)日:1994-09-30

    申请号:JP5024793

    申请日:1993-03-11

    Applicant: IBM

    Abstract: PURPOSE: To enhance resistance against fault like power cutoff, etc., in a semiconductor disk device which uses a batch erasure type non-volatile memory. CONSTITUTION: A batch erasure type non-volatile memory contains plural sectors and attribute information for recognizing their own attribute is written in every sector. As a rule, a cluster information sector is placed at the front position of a cluster to which it belongs. Then, data sector is placed in a data area which is an area except the front position of a cluster. A controller connected to the memory produces a cluster information copy sector in a data are at the time of cluster erasure, reconstitutes cluster management information from the cluster information copy sector and produces a cluster information sector at the time of cluster initialization.

    BATCHED-ERASURE NONVOLATILE SEMICONDUCTOR MEMORY DEVICE

    公开(公告)号:JPH06111589A

    公开(公告)日:1994-04-22

    申请号:JP24311892

    申请日:1992-09-11

    Applicant: IBM

    Abstract: PURPOSE: To obtain the efficient redundant constitution of a batch erasing type nonvolatile semiconductor storage device. CONSTITUTION: The array of a memory cell 31 is physically divided into a data area 36 and a tag area 37 to separately batch-erase the respective areas while sharing a word line 32. In the unit of the areas 36 and 37 sharing one word line, the area 37 holds positional information of a defective memory cell in the area 36. Based on this information, a system executes the using avoiding processing of the defective memory cell. Defective memory cell information is programmed in an inspection process after producing a chip, and ECC is written in the area 37 with respect to this defective memory cell information. By writing fixed data in the area 37, the using prohibition of the area 36 sharing the word line with the area 37 is reported to the system. Even when the area 36 is batch-erased, the area 37 is not erased and defective memory cell positional information is held.

    DRIVING METHOD OF MR HEAD AND HARD-DISK SYSTEM

    公开(公告)号:JPH087203A

    公开(公告)日:1996-01-12

    申请号:JP13983794

    申请日:1994-06-22

    Applicant: IBM

    Abstract: PURPOSE: To enhance easily the stability of a magnetic domain of a MR head without carrying out complicated works such as disassembling and assembling etc. and reproduce data. CONSTITUTION: A drive device 28 is driven corresponding to a signal output from a controller body 40 of a HDC 30, and it records and reproduces data in a location where an access arm is pivoted at a specific angle. When data for this disk are recorded and reproduced, a bias current supplied to a reproduction element 21A of a magnetic head 20A having a MR effect is turned on/off only for a specific period by a reproduction control circuit 32A. Accordingly, as a direction of a magnetizing vector is changed within a specific period, a magnetic domain of the reproduction element 21A (MR element) is not unstable, but stabilized so that data from the disk can be reproduced stably.

    BATCH ERASURE TYPE NONVOLATILE MEMORY AND SEMICONDUCTOR DISK DEVICE USING IT

    公开(公告)号:JPH06250798A

    公开(公告)日:1994-09-09

    申请号:JP3522893

    申请日:1993-02-24

    Applicant: IBM

    Abstract: PURPOSE: To discriminate an invalid sector from a valid sector without using a method for overwriting by ensuring a cluster information sector in each cluster, applying a sequence number to the cluster so as not to be doubled, and writing the sequence number assigned to the cluster in the cluster information sector of each cluster. CONSTITUTION: A batch delete type nonvolatile memory 20 can be deleted by each cluster unit, a cluster information sector is ensured in each of the N pieces of clusters, a sequence number is preliminarily applied to the N pieces of clusters so as not to be overlapped, and the sequence number of the cluster is written in the cluster information sector of each cluster. At the time of deleting a certain cluster, a controller 30 maintains the sequence number of the cluster at first, and at the time of initializing the deleted cluster, the controller 30 writes a value larger than the present maximum sequence number in the cluster information sector as the sequence number of the cluster. The controller 30 writes user data according to the sequence number of the physical address of the sector.

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