Fujitsu Corporation

Toshiba Storage Device Corporation

Tsugito Maruyama

Yuichi Sato

Mitsunori Hirata

Shinji Kanda

Jun Wakitani

Toshihiko Morita

Sumio Kuroda

Arata Ejiri

Hiroyuki Suzuki

Kazuhiko Takaishi

Tomoyoshi Yamada

Yuhei Umeda

Hirokazu Anai

Fumio Nagashima

Masanori Fukushi

Naozumi Tsuda

Yoshiyasu Nakashima

Yu Yonezawa

Ichiro Watanabe

Tomotake Sasaki

Hironori Teguri

Hiroyuki Kubotera

Takashi Uchiyama

Keishi Hanahara

A control device includes: a power supply circuit that controls output voltage using a switching element; a generation unit that generates a reference signal on the basis of the output voltage from the power supply circuit; a PWM unit that generates a PWM signal that is output to the switching element by comparing the reference signal with a carrier signal; and a switching unit that switches a frequency of the carrier signal by changing amplitude of the carrier signal, wherein the generation unit generates the reference signal on the basis of the frequency.

Control device, control method, and power supply device

In this disclosure, equations to be solved in the model predictive control are transformed by using an off-line algebraic simplification method into a matrix operational expression representing a product of a coefficient matrix and a vector regarding solution inputs within a control horizon is equal to a function vector regarding target values of output states and the output states. The size of the coefficient matrix is reduced compared with the conventional matrix. Then, the matrix operational expression is solved in an online plant control apparatus with present output states and present target values of the output stats of a plant to be controlled, by the direct method, to output the solution to the plant.

Matrix generation technique and plant control technique

By using a model of a transient response characteristic of an engine and a model of a steady-state characteristic of the engine, a disturbance estimate value is calculated. By using this disturbance estimate value, initial command values of a nozzle opening degree of a Variable Nozzle Turbo and a valve opening degree of a Exhaust Gas Recirculator are adjusted in order to reduce model errors and appropriately handle the disturbance. Hence, it is possible to cause Mass Air Flow and Manifold Air Pressure to follow their target values stably.

Engine control apparatus and method

Setting values of a fuel injection quantity for an engine having an exhaust gas recirculator (EGR) and variable nozzle turbo (VNT), and an engine speed, and measurement values of a manifold air pressure (MAP) and a mass air flow (MAF) are obtained. According to a combination of the reference values of an EGR valve opening degree and a VNT nozzle opening degree, which correspond to the setting values, or a combination of a control value of the EGR valve opening degree by a MAF controller and a control value of the VNT nozzle opening degree by a MAP controller, which correspond to the measurement values, a mode that the MAF and MAP controllers, a first interference compensator from the MAF controller to the MAP controller and a second interference compensator for the reverse direction are enabled and a mode that the MAF or MAP controller is enable are dynamically switched.

Engine control program, method and apparatus

A magnetic storage apparatus has a reproducing head to reproduce information from a perpendicular magnetic recording medium that is recorded with servo information, eccentricity correction data and read/write data. The apparatus further has a filter part to filter a reproduced output of the reproducing head by filtering the servo information which has a differentiated waveform by a non-differentiating characteristic and by filtering the eccentricity correction data and the read/write data which have rectangular waveforms by a differentiating characteristic, a demodulating part to demodulate the servo information, the eccentricity correction data and the read/write data that are filtered by the filter part, and a servo system to carry out a control process including an eccentricity control based on the servo information and the eccentricity correction data that are demodulated.

Eccentricity correction method, signal processing circuit, magnetic storage apparatus and perpendicular magnetic recording medium

A master-disk producing device produces a master disk with master-disk identification information added. A disk producing device produces a first disk with the master-disk identification information added, using the master disk with the master-disk identification information added. A first disk device obtains, after the first disk with the master-disk identification information added is mounted, first correction information from a correction-information storing device based on the master-disk identification information of the first disk.

Disk-device correcting system, information managing device, master-disk producing device, and master-disk producing method

A storing unit stores first correction information for correcting a distortion synchronized with a rotation frequency of servo information of a first disk. A control unit controls positioning of a head on a target track by correcting the servo information of the first disk with the first correction information. Measurement information used for measuring the first correction information is calculated based on second correction information for the servo information in other disk apparatus including a second disk on which the servo information is formed using a common master medium with the first disk.

Disk apparatus, information processing system, and information providing apparatus

The difference is detected between the outputs from first and second heads in a recording medium drive. The first head is positioned relative to the boundary between a first recording track and a separation track isolating the first recording track and a second recording track from each other. The second head is positioned relative to the boundary between the separation track and the second recording track. A position information specifying the positions of the first and second heads are generated based on the difference. The first and second heads follow the different boundaries, so that the outputs of the first and second heads reliably vary. The difference between the outputs thus reliably changes. An accurate position information can be generated based on the difference. The position information may be utilized in tracking servo control, for example. This enables establishment of the tracking servo control with a higher accuracy.

Method of detecting position of head in recording medium drive

A head arm of a magnetic disk device has reduced air flow turbulence around the head arm using one or more of several configurations, such as multiple apertures, various chamfered edges, various protrusion configurations, and head arm shapes.

Head arm of magnetic disk device

A head arm includes a main body, partially located with a first area above a recordable medium. The main body includes a first surface opposite to the recordable medium and a second surface opposite to the first surface. A hole extends through the main body between the first and second surfaces. The main body also has a first connector portion connectible to a driving portion; and a second connector portion connectible to a head. The through hole is formed on only one side with respect to a line that halves the first area between said first and second connector portions.

Head arm having through hole for making head arm lightweight, head moving mechanism and disk unit having the head arm

A disassembly route producing apparatus searches for a disassembly route for disassembling a product into its component parts. In one embodiment, the apparatus selects one of the parts to be disassembled, and determines the closest distance the selected part may approach the remaining parts as the selected part is being moved. The selected part is disassembled through a series of translations in predetermined directions and for predetermined distances. After each translation, the apparatus determines whether the selected part collided with any of the remaining parts. If a collision occurs, the apparatus changes the direction for the translations and resumes the search. A corresponding assembly route is determined by reversing the disassembly route.

Disassembly route producing apparatus, assembly route producing

In an automatic wiring connection apparatus, position detection marks 221; 231 are disposed on matrix boards 220; 230, respectively, as shown in FIG. 8. Position data of a desired crosspoint hole included in anyone of areas 227.sub.-- 1, . . . , 227.sub.-- 5; 237.sub.-- 1, . . . , 237.sub.-- 4 as assembly of crosspoint holes is corrected in accordance with a difference between design values of the position detection marks 221; 231 and measured values. A pin insertion and pulling out robot is operated in accordance with the corrected position data.

Automatic wiring connection apparatus

An interference checking method for checking the interference between two objects in the shape of non-convex polyhedrons, comprising the steps of producing a convex hull for each of the non-convex polyhedrons, and checking the interference of the convex hull of one object with the convex hull of the other object; covering each of polygons which constitute each of the non-convex polyhedrons with a plurality of leaf spheres which have a predetermined radius and which are arranged on each polygon when the distance between the convex hulls becomes not more than a preset value, and sequentially enveloping the leaf spheres with hierarchical spheres so as to produce a binary tree of hierarchical envelope spheres; obtaining a pair of nearby spheres closest by checking the interference between envelope spheres of an upper grade on the basis of the structure of the binary tree, disassembling the interfering envelope spheres into envelope spheres of a lower grade, checking the interference between the envelope spheres of the lower grade, and repeating the interference check process and the disassembly process until no interference is detected; obtaining a nearby polygon pair which corresponds to the pair of nearby spheres; and checking the interference between the nearby polygon pair.

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Kawasaki, Japan

Tsugito Maruyama