Toshio Suzuki

Bio: Toshio Suzuki is an academic researcher from Tohoku University. The author has contributed to research in topics: Solenoid & Electromagnet. The author has an hindex of 12, co-authored 76 publications receiving 477 citations. Previous affiliations of Toshio Suzuki include Hitachi & TRIUMF.

Controller for electric vehicle

Abstract: The present invention relates to a controller for an electric vehicle in which right and left drive wheels are respectively driven by drive motors which are individually provided. The controller for an electric vehicle comprises motors for driving right and left wheels, means for detecting rotating speeds or rotation torques of the wheels, and a facility for taking a rotation deviation between output signals from the detection means close to zero. As a result, the vehicle is always operated in safety.

Automatic change-gear control device for use in electromobile

Abstract: An electromobile equipped with an automatic transmission which may detect a running condition of a vehicle and selects a gear ratio suited for the running condition. In this electromobile, a build-up characteristic of an electric motor current immediately after gear-change is improved, thereby minimizing delay in power transmission so as to shorten a gear-changing duration, in an attempt to improve an operational feeding of a driver at the time of gear change.

Method of and apparatus for converting design pattern data to exposure data

Abstract: A method and apparatus for converting design pattern data for a semiconductor integrated circuit device to an exposure data for use in an exposure apparatus The pattern data includes a repetition data section corresponding to the repetition section and defining one or more repetitive pattern segments for the unit cells with an overlap between adjacent ones of repetitive pattern segments and a non-repetition data section corresponding to the non-repetition section Repetition information specifying the repetitive pattern segment is first produced from the design pattern data, and a pattern segment repetition frame is determined on the basis of the repetition information The pattern segment repetition frame defines a unit region selected from the repetitive pattern segment A repetitive arrangement of the unit region without any overlap is equivalent to at least a portion of the repetition section Data for one of the unit cells and those of unit cells which are adjacent the one unit cell are selected and developed on the basis of the repetition information and are pattern-processed to produce processed repetitive pattern segment data and that portion of the processed repetitive pattern segment data which lies within the pattern segment repetition frame is extracted to form a fundamental pattern segment data The fundamental pattern segment data is repetitively used for drawing the repetition section

Rectifier control apparatus with improved power factor

Abstract: A single phase, full wave diode bridge circuit is connected with a chopper on its DC output side. An output voltage of the chopper is smoothed by a smoothing capacitor and thereafter supplied for a load. A current control apparatus forms a current reference signal which is synchronized with an AC voltage applied to the bridge circuit and has a magnitude corresponding to a current flowing through the load and produces a deviation signal between the current reference signal and an actual AC input current of the bridge circuit. The chopper is controlled in accordance with the deviation signal so that the AC input current follows the current reference signal, whereby the power factor and the waveform of the AC input current in the bridge circuit are improved.

Construction and testing of a 3 m diameter × 5 m superconducting solenoid for the fermilab collider detector facility (CDF)

Abstract: A thin 3 m diameter × 5 m, 15 T superconducting solenoid for the Fermilab collider detector facility (CDF solenoid) was constructed Cool-down and excitation tests of the solenoid were carried out The design current is 5000 A and the stored magnetic energy is 30 × 106 J The solenoid utilizes the forced flow cooling method of two-phase helium and does not have a permanent inner bobbin The material thickness of the solenoid is 085 radiation length in the radial direction An aluminum-stabilized NbTi/Cu superconductor fabricated with the EFT method was used Radially outward magnetic forces must be supported with an outer support cylinder shrink-fitted outside the coil The helium cooling tube of 20 mm in inner diameter and about 140 m in length was welded to the outer support cylinder The maximum excitation current was limited to 2800 A in the present tests without an iron return yoke Thermal response of the solenoid during the cool-down and excitation tests was very steady A series of heater quench tests was attempted by using a heater installed at the outer support cylinder The solenoid did not quench even for a heater input of about 10 kJ In a warm-up test the liquid helium supply was shut off The coil stayed superconducting for about 90 min and then the entire coil became normal very uniformly This result is consistent with the measured heat load of the solenoid of about 35 W The results of the present tests indicate the excellent thermal stability of the solenoid

The shell model as a unified view of nuclear structure

Abstract: The last decade has witnessed both quantitative and qualitative progresses in Shell Model studies, which have resulted in remarkable gains in our understanding of the structure of the nucleus. Indeed, it is now possible to diagonalize matrices in determinantal spaces of dimensionality up to 10^9 using the Lanczos tridiagonal construction, whose formal and numerical aspects we will analyze. Besides, many new approximation methods have been developed in order to overcome the dimensionality limitations. Furthermore, new effective nucleon-nucleon interactions have been constructed that contain both two and three-body contributions. The former are derived from realistic potentials (i.e., consistent with two nucleon data). The latter incorporate the pure monopole terms necessary to correct the bad saturation and shell-formation properties of the realistic two-body forces. This combination appears to solve a number of hitherto puzzling problems. In the present review we will concentrate on those results which illustrate the global features of the approach: the universality of the effective interaction and the capacity of the Shell Model to describe simultaneously all the manifestations of the nuclear dynamics either of single particle or collective nature. We will also treat in some detail the problems associated with rotational motion, the origin of quenching of the Gamow Teller transitions, the double beta-decays, the effect of isospin non conserving nuclear forces, and the specificities of the very neutron rich nuclei. Many other calculations--that appear to have ``merely'' spectroscopic interest--are touched upon briefly, although we are fully aware that much of the credibility of the Shell Model rests on them.

Variable current limit control for vehicle electric drive system

Abstract: A vehicle electric drive system includes an internal combustion engine, an electric motor/generator driven by the engine, a first inverter/rectifier coupled to motor/generator, a bus coupled to the first inverter/rectifier, a second inverter/rectifier coupled to the bus, and a traction motor/generator coupled to an output of the second inverter/rectifier, an operator speed control member, and a controller coupled to the second inverter/rectifier for controlling a current output of the second inverter/rectifier as a function of a position of the speed control member Also included is an operator controlled foot pedal and a transducer coupled to the foot pedal and generating a signal representing foot pedal position which is supplied to the controller The controller limits current supplied by the second inverter/rectifier to the traction motor/generator to a limit current as a function of the transducer signal The controller, foot pedal and transducer cooperate to vary the limit current in response to movement of the foot pedal A spring biases the foot pedal to an upper limit position The controller causes the second inverter/rectifier to supply to the traction motor/generator a maximum amount of current, (such maximum current being a function of the foot pedal position), but not more than that required to achieve the speed commanded by the speed control

Electric power-steering device

Abstract: An electric power-steering device has a speed-reducing mechanism (17) for reducing the speed of an output shaft (16) of an electric motor (15). The speed-reducing mechanism (17) has an internal gear (39) engaged and rotated with the output shaft (16) and an external gear (40) with which the internal gear (39) internally meshes. A drive pulley (41) rotatable together with the external gear (40) and a driven pulley (42) provided so as to surround a steering shaft are connected by an endless belt (43). Speed reduction is obtained by the internal gear (39) and the external gear (40), and the speed-reducing mechanism (17) as a whole achieves a high reduction ratio without greatly reducing the diameter of the drive pulley (41).

High-precision measurement of the W boson mass with the CDF II detector

Abstract: The mass of the W boson, a mediator of the weak force between elementary particles, is tightly constrained by the symmetries of the standard model of particle physics. The Higgs boson was the last missing component of the model. After observation of the Higgs boson, a measurement of the W boson mass provides a stringent test of the model. We measure the W boson mass, MW, using data corresponding to 8.8 inverse femtobarns of integrated luminosity collected in proton-antiproton collisions at a 1.96 tera–electron volt center-of-mass energy with the CDF II detector at the Fermilab Tevatron collider. A sample of approximately 4 million W boson candidates is used to obtain MW=80,433.5±6.4stat±6.9syst=80,433.5±9.4 MeV/c2, the precision of which exceeds that of all previous measurements combined (stat, statistical uncertainty; syst, systematic uncertainty; MeV, mega–electron volts; c, speed of light in a vacuum). This measurement is in significant tension with the standard model expectation. Description Weighing the W boson W bosons mediate the weak interaction, one of the fundamental forces in physics. Because the Standard Model (SM) of particle physics places tight constraints on the mass of the W boson, measuring the mass puts the SM to the test. The Collider Detector at Fermilab (CDF) Collaboration now reports a precise measurement of the W boson mass extracted from data taken at the Tevatron particle accelerator (see the Perspective by Campagnari and Mulders). Surprisingly, the researchers found that the mass of the boson was significantly higher than the SM predicts, with a discrepancy of 7 standard deviations. —JS Analysis of the data collected at the Tevatron particle collider finds that the W boson is heavier than expected.

The CDF Detector: An Overview

Abstract: The Collider Detector at Fermilab (CDF) is a 5000 t magnetic detector built to study 2 TeV p p collisions at the Fermilab Tevatron. Event analysis is based on charged particle tracking, magnetic momentum analysis and fine-grained calorimetry. The combined electromagnetic and hadron calorimetry has approximately uniform granularity in rapidity-azimuthal angle and extends down to 2° from the beam direction. Various tracking chambers cover the calorimeter acceptance and extend charged particle tracking down to 2 mrad from the beam direction. Charged particle momenta are analyzed in a 1.5 T solenoidal magnetic field, generated by a superconducting coil which is 3 m in diameter and 5 m in length. The central tracking chamber measures particle momenta with a resolution better then δpT/pT2 = 2 × 10−3 (GeV/c)−1 in the region 40°