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公开(公告)号：DE3484637D1
公开(公告)日：1991-07-04
申请号：DE3484637
申请日：1984-08-10
Applicant: IBM
Inventor： TUNG MIN-HSIUNG GEORGE , YANAGISAWA HIROSHI
Abstract: An image scaling method and apparatus partitions each line of image pel (print element) indicating bits into a number of bit groups equal to the number of bits to be added or deleted from the line to achieve a desired scaling. In each of the bit groups, one pel is added for enlargement or one pel is deleted for reduction. The pel addition or deletion occurs at pairs of like-pel indicating bits. If any bit groups has no pairs of like-pel indicating bits, a pel indicating bit is added for enlargement or deleting for reduction in an arbitrary location in the bit group.
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公开(公告)号：DE3371127D1
公开(公告)日：1987-05-27
申请号：DE3371127
申请日：1983-08-31
Applicant: IBM
Inventor： KIDA MASUYOSHI , TUNG MIN-HSIUNG GEORGE , USHIRODA TATSUYUKI , CANNISTRA ANTHONY T
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公开(公告)号：DE3782328T2
公开(公告)日：1993-04-22
申请号：DE3782328
申请日：1987-12-18
Applicant: IBM
Inventor： ABRAHAM DENNIS GEORGE , DOUBLE GLEN PAUL , NECKYFAROW STEVEN WILLIAM , ROHLAND WILLIAM STANLEY , TUNG MIN-HSIUNG GEORGE
Abstract: A smart card (10) which has a instruction processor (12) which is connected to a changeable memory (16) in which application programs are stored. The card is manufactured partially blank, or without an application program stored thereon, and an application program is then loaded into the changeable memory, i.e., by downloading it from a mainframe computer. In this manner, the application program in a smart card may be changes by an authorized party. Further, a flag (22) indicates whether a program has been loaded on a smart card. Also disclosed is a method of securing the program from tampering by unauthorized parties where, in response to certain instructions (such as a dump of the application program), key portions are erased prior to execution. Application programs are loaded onto the card through the use of a double timed reset, the first of which writes a predetermined sequence on the card for a set time interval. The second reset before the end of the set time interval then indicates that a program load function is to occur and causes key selected portions of the memory to be overwritten and erased to protect key data from the previous program from being maintained or used later.
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公开(公告)号：DE3782328D1
公开(公告)日：1992-11-26
申请号：DE3782328
申请日：1987-12-18
Applicant: IBM
Inventor： ABRAHAM DENNIS GEORGE , DOUBLE GLEN PAUL , NECKYFAROW STEVEN WILLIAM , ROHLAND WILLIAM STANLEY , TUNG MIN-HSIUNG GEORGE
Abstract: A smart card (10) which has a instruction processor (12) which is connected to a changeable memory (16) in which application programs are stored. The card is manufactured partially blank, or without an application program stored thereon, and an application program is then loaded into the changeable memory, i.e., by downloading it from a mainframe computer. In this manner, the application program in a smart card may be changes by an authorized party. Further, a flag (22) indicates whether a program has been loaded on a smart card. Also disclosed is a method of securing the program from tampering by unauthorized parties where, in response to certain instructions (such as a dump of the application program), key portions are erased prior to execution. Application programs are loaded onto the card through the use of a double timed reset, the first of which writes a predetermined sequence on the card for a set time interval. The second reset before the end of the set time interval then indicates that a program load function is to occur and causes key selected portions of the memory to be overwritten and erased to protect key data from the previous program from being maintained or used later.
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