Abstract: From an ion source and accelerator an ion beam is generated, this ion beam is let go through a circular hole bored in the center of a detector and orifices to irradiate a sample in a sample chamber. The detector detects particles scattered from the sample and arrived at the detector through the orifices. With exhaust units and orifices, the region surrounding the detector is exhausted to be a prescribed degree of vacuum of higher vacuum than the inside of the sample chamber.

Abstract: A method for simulating a stochastic phenomenon, particularly one employing a Monte Carlo method, includes a step for generating random numbers having a nonuniform density function &rgr;(x) based on an ideal model of a chaotic dynamic system in the form Xn+1=f(Xn). The ideal model of chaotic map F(x) is a class of an algebraic map derived from an addition theorem of an elliptic function. The nonuniform density function &rgr;(x) is expressed by an algebraic function of a dynamical variable x. Examples of the ideal model of the chaotic map F(x) include a generalized Ulam-von Neumann map and a generalized cubic map. The nonuniform density function &rgr;(x) of the chaotic maps has the form Xn+1=F(Xn). The class of chaotic dynamical systems is ideal in the sense that the invariant measure &rgr;(x)dx satisfies the ergodic property required by the Monte Carlo method. Thus, a statistical simulation can be performed in the same manner as the conventional Monte Carlo method.

Abstract: In a free form machining tool 10 for machining a surface to be machined while bringing the lower end into contact with the surface to be machined by a rotation around an axis z, the tool comprises a spherical tool 12 having a spherical surface machining section 13 on the lower portion, and a bearing 14 for supporting the spherical tool by an axis a of rotation which passes through the center .largecircle. of the spherical surface and is different from the axis. The tool also includes rotating means 16 (for example, a turbine) for rotating the spherical tool around the axis of rotation. Thus, even if the spherical surface machining section comes into contact with the surface to be machined on the axis (radius: 0) of the tool, the spherical surface machining section is rotated around the axis a of rotation which is different from the axis z. Therefore, a peripheral speed of the axis is not zero (0).

Abstract: The elastic modulus of a piezoelectric substance is controlled over a wide range using a simple method. The effective modulus (the real part of the elastic modulus) and the energy loss modulus (the imaginary part of the elastic modulus) of the piezoelectric substance are changed by installing electrodes on the surface of the piezoelectric substance and by connecting a mechanism consisting of one or more circuit elements to each of the electrodes.

Abstract: There is provided a method of three-dimensionally cutting a mold including the steps, in sequence, of (a) rotating a single ball end mill at a rate in the range of 50,000 rpm to 200,000 rpm, the ball end mill being made of material having high thermal resistance, (b) driving the ball end mill in horizontal, reciprocating movement at a rate in the range of 10 m/min to 100 m/min, and driving the ball end mill in transverse movement at a predetermined depth of cut in a direction perpendicular to a direction in which the ball end mill is reciprocated, at opposite ends of the reciprocating movement to cut a workpiece in a surface thereof at a common depth of cut, and (c) vertically feeding the ball end mill at a predetermined depth of cut. This method makes it possible to significantly increase a rotation speed and a feeding speed of a cutting tool to thereby remarkably reduce time necessary for cutting a mold.

Abstract: There is provided an apparatus for solidifying and shaping fluid which can be optically cured, including (a) an optically scanning device for scanning a level of fluid which can be optically cured, with a light beam, (b) a sinking device for sinking a layer having been cured by scanning carried out by the optically scanning device, below a level of the fluid, and (c) a recoat device for covering a cured layer having been sunk in the step (b), with a fluid which is not yet cured. The recoat device is formed with a recoater blade which horizontally moves above a level of the cured layer with a predetermined gap kept therebetween to smooth a level of the not yet cured fluid. The optically scanning device scans a level of not yet cured fluid having been smoothed by the recoater blade, with a light beam, simultaneously with scanning of the optically scanning device.

Abstract: A magnetoencephalograph comprising an oxide superconductor magnetic shielded vessel and a cryostat for cooling the magnetic shielded vessel, a multichannel SQUID and a cryostat for cooling the SQUID inserted together in the magnetic shielded vessel from one end of the magnetic shielded vessel, a magnetic-field detection unit situated in the vessel for detecting magnetic fields, and a coupling portion for coupling the SQUID and the magnetic-field detection unit with respect to the signals, and the SQUID and the magnetic-field detection unit being detachable. The magnetoencephalograph makes possible the detection of the very weak magnetic fields from the human brain and therewith reduction of the diameter of the opening of the magnetic shield vessel for inserting the SQUID. The reduction of the diameter of the SQUID opening in turn makes it possible to reduce the length of the magnetic shielded vessel, thereby preserving a high shielding effect of the magnetic shield vessel because of the L/D relationship.