Abstract: An information processing apparatus according to an embodiment includes an acquisition unit and a prediction unit. The acquisition unit acquires user information including a number of distributions of an advertisement content to a user targeted for advertisement distribution. The prediction unit predicts an advertising effect of the advertisement content when the advertisement content is distributed to the user, based upon the user information acquired by the acquisition unit.

Abstract: Embodiments of the present invention provide a head stack assembly and a manufacturing method thereof in which manufacturing costs as a multi-disc magnetic device are reduced by increasing the yield and reducing inventory of magnetic heads which can be assembled to the head stack assembly. According to one embodiment, a head stack assembly and a manufacturing method thereof includes plural actuator arms to which magnetic heads are assembled through suspensions. The tolerance of the core width or the write element width of the magnetic heads assembled to inside actuator arms of the plural actuator arms is set to be narrower than the tolerance of the core width or the write element width of the magnetic heads assembled to the outside actuator arms.

Abstract: A method for manufacturing a hard-disk drive (HDD). The method for manufacturing a HDD includes writing servo tracks, and writing servo tracks into the HDD using a calculated control target value of a calculated servo pattern overlap amount. Writing servo tracks includes a first, second, third and fourth operation. The first operation includes: producing a first control equation for obtaining a servo pattern overlap amount; and, converting a root-mean-square error (RMSE) into a probability distribution. The second operation includes calculating a second control target value that results in an increased product yield, from the RMSE probability distribution. The third operation includes producing a second control equation for obtaining a calculated servo pattern overlap amount, by assigning the second control target value into the first control equation.

Abstract: A servo write method for a hard-disk drive. The method includes generating, with an input of characteristics of a magnetic-recording head and a magnetic-recording disk which are incorporated into the hard-disk drive, a yield prediction model from a correlation between yields of the hard-disk drive, and characteristics of the magnetic-recording head and the magnetic-recording disk of the hard-disk drive in a process. The method also includes predicting a yield which is obtained when each magnetic-recording head is used as a position control head, selecting as the position control head a magnetic-recording head that has a highest predicted yield, and writing a servo signal.

Abstract: A method for manufacturing a hard-disk drive (HDD). The method for manufacturing a HDD includes writing servo tracks, and writing servo tracks into the HDD using a calculated control target value of a calculated servo pattern overlap amount. Writing servo tracks includes a first, second, third and fourth operation. The first operation includes: producing a first control equation for obtaining a servo pattern overlap amount; and, converting a root-mean-square error (RMSE) into a probability distribution. The second operation includes calculating a second control target value that results in an increased product yield, from the RMSE probability distribution. The third operation includes producing a second control equation for obtaining a calculated servo pattern overlap amount, by assigning the second control target value into the first control equation.

Abstract: A servo write method for a hard-disk drive. The method includes generating, with an input of characteristics of a magnetic-recording head and a magnetic-recording disk which are incorporated into the hard-disk drive, a yield prediction model from a correlation between yields of the hard-disk drive, and characteristics of the magnetic-recording head and the magnetic-recording disk of the hard-disk drive in a process. The method also includes predicting a yield which is obtained when each magnetic-recording head is used as a position control head, selecting as the position control head a magnetic-recording head that has a highest predicted yield, and writing a servo signal.

Abstract: Embodiments of the present invention provide a data group for each parameter that is classified into a first group and a second group, based on the performance of the products, a base point of a distribution of the data group is calculated, based on the distribution, and a distance range from the base point is decided. The number of data within this range belonging to the first group is counted and substituted for variable FX, the number of data belonging to the second group is counted and substituted for variable SX, the number of data outside this certain range belonging to the first group is counted and substituted for variable FY, and the number of data belonging to the second group is counted and substituted for variable SY. Moreover, a failure content ratio is calculated from variables FX, FY, SX and SY, and the yield impact is calculated.

Abstract: Embodiments of the present invention provide a head stack assembly and a manufacturing method thereof in which manufacturing costs as a multi-disc magnetic device are reduced by increasing the yield and reducing inventory of magnetic heads which can be assembled to the head stack assembly. According to one embodiment, a head stack assembly and a manufacturing method thereof includes plural actuator arms to which magnetic heads are assembled through suspensions. The tolerance of the core width or the write element width of the magnetic heads assembled to inside actuator arms of the plural actuator arms is set to be narrower than the tolerance of the core width or the write element width of the magnetic heads assembled to the outside actuator arms.

Abstract: Embodiments in accordance with the present invention provide a data analysis method that can estimate quantitatively how much the yield is increased by improving a manufacturing process by quantifying a yield impact on the yield of the product. A data group provided for each parameter is classified into a first group and a second group, based on the performance of the products, for each parameter, a base point of a distribution of the data group is calculated, based on the distribution, and a range of certain distance from the base point is decided. The number of data within this certain range belonging to the first group is counted and substituted for the variable FX, the number of data belonging to the second group is counted and substituted for the variable SX, the number of data outside this certain range belonging to the first group is counted and substituted for the variable FY, and the number of data belonging to the second group is counted and substituted for the variable SY.