公开(公告)号：US20010030887A1

公开(公告)日：2001-10-18

申请号：US09866851

申请日：2001-05-30

Applicant: Hitachi, Ltd.

Inventor： Chiaki Ishikawa ,  Kaori Totsuka ,  Yoshio Suzuki

IPC: G11C011/02

CPC classification number: B82Y25/00 ,  B82Y10/00 ,  G01R33/093 ,  G11B5/09 ,  G11B5/3903 ,  G11B5/3954 ,  G11B5/3967 ,  G11B5/40 ,  G11B2005/3996

Abstract: A giant magnetoresistive sensor which is improved in reproduction output and peak asymmetry of read-back waveform. It is composed of a first free ferromagnetic film, a first non-magnetic film, a composite ferromagnetic film, a second non-magnetic film, and a second free ferromagnetic film, which are laminated sequentially, but has no antiferromagnetic film to fix said composite ferromagnetic film, and said composite ferromagnetic film contains a first, second, and third ferromagnetic film, which are antiferromagnetically coupled with one another, and also contains films which separate said ferromagnetic films from one another and antiferromagnetically couple them with one another.

公开(公告)号：US20040193583A1

公开(公告)日：2004-09-30

申请号：US10637556

申请日：2003-08-11

Applicant: Hitachi, Ltd.

Inventor： Yoshio Suzuki ,  Shinji Fujiwara ,  Tsunehiko Baba

IPC: G06F007/00

CPC classification number: G06F11/2097 ,  G06F11/1474 ,  G06F11/2038 ,  Y10S707/959 ,  Y10S707/99952 ,  Y10S707/99953 ,  Y10S707/99955

Abstract: A method for duplicating transactions in a disaster recover system is disclosed. In this method, transactions and queries input to a primary database system are copied to a secondary database system and both database systems execute the queries and save the results permanently to each database, thereby maintaining duplicated data. When executing a query on the primary database system, if the query is a commit, the primary system simultaneously copies uncopied queries placed in a queue to the secondary database system and then executes the query. By using this processing procedure, the invention realizes a disaster recovery system which carries out copying transactions from one site to another site without losing the transactions, while reducing the influence of copy operation on the transaction processing performance.

Abstract translation: 公开了一种在灾难恢复系统中复制事务的方法。 在这种方法中，将输入到主数据库系统的事务和查询复制到辅助数据库系统，并且两个数据库系统都执行查询并将结果永久保存到每个数据库，从而保留重复的数据。 当在主数据库系统上执行查询时，如果查询是提交，则主系统会同时将放入队列中的未查找的查询复制到辅助数据库系统，然后执行查询。 通过使用该处理过程，本发明实现了在不丢失事务的情况下执行从一个站点到另一站点的复制事务的灾难恢复系统，同时减少了复制操作对事务处理性能的影响。

公开(公告)号：US20040186829A1

公开(公告)日：2004-09-23

申请号：US10751419

申请日：2004-01-06

Applicant: Hitachi, Ltd.

Inventor： Yoshio Suzuki ,  Shinji Fujiwara

IPC: G06F017/30

CPC classification number: G06F17/30445 ,  G06F17/30306 ,  G06F17/30566 ,  Y10S707/99931 ,  Y10S707/99932 ,  Y10S707/99933 ,  Y10S707/99934 ,  Y10S707/99935

Abstract: An object of the present invention is to avoid contention for resources in a parallel/decentralized database system so as to improve the performance of the system. A query posing method is implemented in a database system comprising a plurality of database servers each of which includes a database from which the same content can be retrieved and searches the database in response to a query request a front-end server that poses a query according to a predetermined rule and a management server that manages rules to be used by the front-end server. The management server acquires a processed query log relevant to a database server, and produces a rule according to the compatibility value of a query calculated using the acquired processed query log. Moreover, the front-end server poses the query according to the rule produced by the management server.

Abstract translation: 本发明的目的是避免对并行/分散数据库系统中的资源的争用，从而提高系统的性能。 查询构成方法在包括多个数据库服务器的数据库系统中实现，每个数据库服务器包括数据库，从该数据库中可以检索相同的内容，并且响应于查询请求搜索数据库，根据查询请求提供查询的前端服务器 到预定规则和管理由前端服务器使用的规则的管理服务器。 管理服务器获取与数据库服务器相关的处理的查询日志，并根据使用获取的已处理查询日志计算的查询的兼容性值生成规则。 此外，前端服务器根据管理服务器生成的规则提出查询。

公开(公告)号：US20040106009A1

公开(公告)日：2004-06-03

申请号：US10601979

申请日：2003-06-24

Applicant: Hitachi, Ltd.

Inventor： Atsushi Nakamura ,  Yoshio Suzuki ,  Kiwamu Tanahashi ,  Yuko Tsuchiya

IPC: G11B005/66

CPC classification number: G11B5/1278 ,  G11B5/012 ,  G11B5/02 ,  G11B5/09 ,  G11B5/11 ,  G11B5/488 ,  G11B5/4886 ,  G11B5/64 ,  G11B5/74 ,  G11B5/82 ,  G11B2005/0002 ,  G11B2005/0005 ,  G11B2005/0029 ,  Y10T428/11

Abstract: A magnetic recording apparatus provides improved resolution and S/N without adversely affecting thermal stability. An angle formed by the direction of easy magnetization of a recording layer and the direction normal to a magnetic recording medium is in the range between 5null and 55null, the easy magnetization direction is from a back surface of the recording layer toward a front surface thereof, and when a recording track direction is from the upstream of the direction of transportation of the medium toward the downstream thereof, an angle formed by the direction of a projection of the easy magnetization direction on the medium plane and the recording track direction is in the range between 0null and 70null.

Abstract translation: 磁记录装置提供改进的分辨率和S / N，而不会不利地影响热稳定性。 由记录层容易磁化的方向和垂直于磁记录介质的方向形成的角度在5°和55°之间的范围内，容易的磁化方向是从记录层的背面向前表面 并且当记录轨道方向从介质的传送方向的上游到其下游时，由介质平面上的容易磁化方向的投影方向和记录轨道方向形成的角度在 范围在0°和70°之间。