Abstract: According to one embodiment, a magnetic disk device includes a disk, a head, a command queue, a command residence time calculation unit calculating a residence time of each of commands in the command queue, a command information calculation unit calculating the number of the commands and a ratio, a limit time determination unit obtaining a latency limit time corresponding to the number of commands and the ratio, from a latency limit time determination table, and a command selection processing unit selecting a command to be executed, by considering the latency limit time.

Abstract: According to one embodiment, a magnetic disk device includes a disk, a head, a command queue, a command residence time calculation unit calculating a residence time of each of commands in the command queue, a command information calculation unit calculating the number of the commands and a ratio, a limit time determination unit obtaining a latency limit time corresponding to the number of commands and the ratio, from a latency limit time determination table, and a command selection processing unit selecting a command to be executed, by considering the latency limit time.

Abstract: The present invention provides a hydrogenation catalyst, which can produce an olefin polymer having a higher molecular weight, and a process for producing an olefin polymer having a higher molecular weight, by controlling hydrogen concentration in a polymerization reaction system efficiently in polymerizing an olefin in the presence of hydrogen. There is provided a hydrogenation catalyst formed by contacting the undermentioned component (A), the undermentioned component (B), and the undermentioned component (C). There is further provided a process for producing an olefin polymer characterized by polymerizing an olefin in the presence of hydrogen, the undermentioned component (A), the undermentioned component (B), and the undermentioned component (D). Component (A): a titanocene compound; Component (B): a silicon compound represented by the undermentioned general formula [1]: Si(OR1)4 [1]; Component (C): an alkyl metal compound; Component (D): a catalyst for olefin polymerization.

Abstract: The present invention provides a hydrogenation catalyst, which can produce an olefin polymer having a higher molecular weight, and a process for producing an olefin polymer having a higher molecular weight, by controlling hydrogen concentration in a polymerization reaction system efficiently in polymerizing an olefin in the presence of hydrogen. There is provided a hydrogenation catalyst formed by contacting the undermentioned component (A), the undermentioned component (B), and the undermentioned component (C). There is further provided a process for producing an olefin polymer characterized by polymerizing an olefin in the presence of hydrogen, the undermentioned component (A), the undermentioned component (B), and the undermentioned component (D). Component (A): a titanocene compound; Component (B): a silicon compound represented by the undermentioned general formula [1]: Si(OR1)4 [1]; Component (C): an alkyl metal compound; Component (D): a catalyst for olefin polymerization.

Abstract: The purpose of the present invention is provite a process for producing an olefin polymer, which can produce an olefin polymer having a higher molecular weight even in the presence of hydrogen and can obtain an olefin polymer having good powder characteristics by lowering hydrogen concentration efficiently in polymerizing an olefin in the presence of hydrogen by use of a gas phase reaction vessel. There is provided a process for producing an olefin polymer comprising the steps of: using a gas phase reaction vessel; polymerizing an olefin by use of a catalyst for olefin polymerization in the presence of hydrogen; adding a hydrogenation catalyst into the gas phase reaction vessel; and adding a polymerization activity depressant.

Abstract: There is provided a high-voltage pulse generator with a reduced radius of rotation and improved performance, and a lighting apparatus and a vehicle having the high-voltage pulse generator. The high-voltage pulse generator includes a pulse transformer in which a primary winding and a secondary winding are wound on a core, a discharge lamp connector which is formed in a tube shape having an opened front surface and a bottom out of an insulating material and which has an inner-electrode terminal electrically connected to a high voltage part of the secondary winding in the bottom, and a pulse generating capacitor and a discharge switch electrically connected to the primary winding of the pulse transformer. The discharge lamp connector is disposed so that the center thereof is located in a center line passing through a substantial center in an axis direction (a direction parallel to a center line) of the pulse transformer and perpendicular to the axis direction.

Abstract: The purpose of the present invention is to provide a process for producing an olefin polymer, which can produce an olefin polymer having a higher molecular weight by lowering hydrogen concentration efficiently in polymerizing an olefin in the presence of hydrogen by use of a gas phase reaction vessel. There is provided a process for producing an olefin polymer comprising the steps of: using a gas phase reaction vessel; polymerizing an olefin by use of a catalyst for olefin polymerization in the presence of hydrogen; and adding a hydrogenation catalyst to a bed portion in the gas phase reaction vessel.

Abstract: The method for producing a propylene-ethylene block copolymer in accordance with the present invention has: a first polymerization process which is performed using two or more polymerization tanks connected in series and in which a solid catalyst or a prepolymerized catalyst containing a solid catalyst, and propylene are continuously supplied to a first polymerization tank; and a second polymerization process in which propylene, ethylene, and polypropylene particles continuously extracted from the last polymerization tank of the first polymerization process are supplied to a polymerization tank to produce a propylene-ethylene block copolymer, wherein the average retention time of the polypropylene particles in each polymerization tank of the first polymerization process is 0.1 to 1.5 h and the sum total of average retention times of polypropylene particles in the polymerization tanks of the first polymerization process is 1.5 to 3.0 h.

Abstract: The purpose of the present invention is to provide a process for producing an olefin polymer, which can produce an olefin polymer having a higher molecular weight by lowering hydrogen concentration efficiently in polymerizing an olefin in the presence of hydrogen by use of a gas phase reaction vessel. There is provided a process for producing an olefin polymer comprising the steps of: using a gas phase reaction vessel; polymerizing an olefin by use of a catalyst for olefin polymerization in the presence of hydrogen; and adding a hydrogenation catalyst to a bed portion in the gas phase reaction vessel.

Abstract: The purpose of the present invention is provite a process for producing an olefin polymer, which can produce an olefin polymer having a higher molecular weight even in the presence of hydrogen and can obtain an olefin polymer having good powder characteristics by lowering hydrogen concentration efficiently in polymerizing an olefin in the presence of hydrogen by use of a gas phase reaction vessel. There is provided a process for producing an olefin polymer comprising the steps of: using a gas phase reaction vessel; polymerizing an olefin by use of a catalyst for olefin polymerization in the presence of hydrogen; adding a hydrogenation catalyst into the gas phase reaction vessel; and adding a polymerization activity depressant.

Abstract: The purpose of the present invention is to provide a hydrogenation catalyst, which can produce an olefin polymer having a higher molecular weight, and a process for producing an olefin polymer so that an olefin polymer having a higher molecular weight can be produced, by controlling hydrogen concentration in a polymerization reaction system efficiently in polymerizing an olefin in the presence of hydrogen. There is provided a hydrogenation catalyst formed by contacting the undermentioned component (A), the undermentioned component (B), and the undermentioned component (C). There is further provided a process for producing an olefin polymer characterized by polymerizing an olefin in the presence of hydrogen, the undermentioned component (A), the undermentioned component (B), and the undermentioned component (D).

Abstract: The method for producing a propylene-ethylene block copolymer in accordance with the present invention has: a first polymerization process which is performed using two or more polymerization tanks connected in series and in which a solid catalyst or a prepolymerized catalyst containing a solid catalyst, and propylene are continuously supplied to a first polymerization tank; and a second polymerization process in which propylene, ethylene, and polypropylene particles continuously extracted from the last polymerization tank of the first polymerization process are supplied to a polymerization tank to produce a propylene-ethylene block copolymer, wherein the average retention time of the polypropylene particles in each polymerization tank of the first polymerization process is 0.1 to 1.5 h and the sum total of average retention times of polypropylene particles in the polymerization tanks of the first polymerization process is 1.5 to 3.0 h.

Abstract: There is provided a high-voltage pulse generator with a reduced radius of rotation and improved performance, and a lighting apparatus and a vehicle having the high-voltage pulse generator. The high-voltage pulse generator includes a pulse transformer in which a primary winding and a secondary winding are wound on a core, a discharge lamp connector which is formed in a tube shape having an opened front surface and a bottom out of an insulating material and which has an inner-electrode terminal electrically connected to a high voltage part of the secondary winding in the bottom, and a pulse generating capacitor and a discharge switch electrically connected to the primary winding of the pulse transformer. The discharge lamp connector is disposed so that the center thereof is located in a center line passing through a substantial center in an axis direction (a direction parallel to a center line) of the pulse transformer and perpendicular to the axis direction.

Abstract: A safety ballast for a discharge lamp capable of interrupting the supply of the electric power upon failure of starting the lamp. The ballast includes a converter providing a DC power voltage from a DC voltage source, a booster providing a boosted DC voltage to a starter which generates, based upon the boosted DC voltage, a starting voltage for starting the lamp, and an inverter receiving the DC power from the converter to provide an AC power for operating the lamp. The booster includes a capacitor which is charged by the DC power and accumulate the boosted voltage. A controller monitors a load condition of the lamp and issues a disable signal when a no-load condition continues over a predetermined starting period. The inverter includes a plurality of switching elements one of which is regulated to be turned on in response to the no-load signal for establishing a supply path of supplying the boosted voltage from the booster's capacitor through the switching element to the starter.