Abstract: A metal junction thermoelectric device includes at least one thermoelectric element. The thermoelectric element has first and second opposite sides, and a first conductor made from a first metal, and a second conductor made from a second metal. The first and second conductors are electrically interconnected in series, and the first and second conductors are arranged to conduct heat in parallel between the first and second sides. The first metal has a first occupancy state, and the second metal has a second occupancy state that is lower than the first occupancy state. A temperature difference between the first and second sides of the thermoelectric element causes a charge potential due to the difference in occupancy states of the first and second metals. The charge potential generates electrical power.

Abstract: Disclosed is a disc-shaped sample chamber for collecting molten metal, the chamber comprising: a chamber body having a left body and a right body bonded to each other to define a disc-shaped sample space therebetween; an inlet extending upward from the chamber body and connecting the sample space with the outside; and a welded bonding portion disposed on at least one lateral face of the chamber body for bonding the left body and the right body to each other. Further, a probe having the chamber is disclosed.

Abstract: Provided are a QR decomposition apparatus and method for a MIMO system. The QR decomposition apparatus includes: a norm calculator for calculating a vector size norm for a channel input; a Q column calculator for calculating a column value of a unitary matrix Q by multiplying a delayed channel input with ?{square root over (norm)}; an R row calculator for receiving the delayed channel input, the output of the Q column calculator, and 1/?{square root over (norm)}, and calculating a row value of an upper triangular matrix R; a Q update calculator for receiving the delayed channel input, the output of the R row calculator, and a delayed output of the Q column calculator, and calculating a Q update matrix value; and a norm update calculator for receiving a delayed output of the norm calculator and an output of the R row calculator, and outputting a norm update matrix value.

Abstract: Provided are a QR decomposition apparatus and method for a MIMO system. The QR decomposition apparatus includes: a norm calculator for calculating a vector size norm for a channel input; a Q column calculator for calculating a column value of a unitary matrix Q by multiplying a delayed channel input with ?{square root over (norm)}; an R row calculator for receiving the delayed channel input, the output of the Q column calculator, and 1/?{square root over (norm)}, and calculating a row value of an upper triangular matrix R; a Q update calculator for receiving the delayed channel input, the output of the R row calculator, and a delayed output of the Q column calculator, and calculating a Q update matrix value; and a norm update calculator for receiving a delayed output of the norm calculator and an output of the R row calculator, and outputting a norm update matrix value.

Abstract: A method for isotope separation of ytterbium comprises isotope-selective photoionizing of a target isotope by use of a laser, and photoionizing of the target isotope from a metastable state to a continuum state or an auto-ionization state through excited states. The photoionized isotope ions of ytterbium can be separated within an electric field. With the method, it is possible to separate a great amount of ytterbium isotope by use of a simple apparatus while ensuring a highly economic efficiency in comparison with a conventional EM method.

Abstract: A method for isotope separation of thallium using a laser beam comprising the steps of: (a) producing photons of a first frequency by a laser system, wherein a wave length of the first frequency is about 378 nm; (b) producing photons of a second frequency by the laser system, wherein a wave length of the second frequency is about 292 nm; (c) producing photons of a third frequency by the laser system, wherein a wave length of the third frequency is in the range of 700 nm to 1400 nm; (d) applying the photons of the first, second and third frequencies to the vapor of the thallium, wherein the photons of the first frequency pump isotope-selectively a plurality of ground state thallium atoms through an excited state into a metastable state, and wherein the photons of the second frequency excite a plurality of metastable state thallium atoms to an intermediate, resonant state, and wherein the photons of the third frequency ionize a plurality of atoms in the intermediate, resonant state through continuum states; and

Abstract: A method for isotope separation of thallium using a laser beam is disclosed.

Abstract: In a laser welding, a laser beam is focused on a workpiece by a focusing lens or lenses. The focusing lens or lenses image an aperture liming the size of the laser beam on the workpiece and the size of focused laser beam is the image size of the aperture on the workpiece at the wavelength of the laser. A weld pool is generated by the interaction of the focused laser beam and the workpiece. Due to the thermal conduction of the workpiece, the size of the weld pool is generally not the same as the size of the focused laser beam and varies with the power of the laser or with the focus shift of the focusing lens or lenses. The weld pool irradiates a thermal radiation. The thermal radiation is measured back through the focusing lens or lenses and through the aperture limiting the size of the laser beam or any other aperture limiting a size of the thermal radiation to be measured in three spectral bands with single element detectors.

Abstract: In a laser welding, a laser beam is focused on a workpiece by a focusing lens or lenses. The focusing lens or lenses image an aperture liming the size of the laser beam on the workpiece and the size of focused laser beam is the image size of the aperture on the workpiece at the wavelength of the laser. A weld pool is generated by the interaction of the focused laser beam and the workpiece. Due to the thermal conduction of the workpiece, the size of the weld pool is generally not the same as the size of the focused laser beam and varies with the power of the laser or with the focus shift of the focusing lens or lenses. The weld pool radiates a thermal radiation. An apparatus and method is disclosed wherein the thermal radiation is measured back through the focusing lens or lenses and through the aperture limiting the size of the laser beam or any other aperture limiting a size of the thermal radiation to be measured in at least three spectral bands with single element detectors.

Abstract: A method and apparatus for real-time weld process monitoring are provided for a pulsed laser welding. The thermal radiation from a weld pool is measured at several spectral bands through an aperture with single-element detectors after splitting the spectral bands with dichromatic mirrors and beam splitters. The distal end of an optical fiber for laser delivery can be used as an aperture and each spectral band signal is measured with a single-element detector. Due to the chromatic aberration of an imaging optics, the field of view from a single-element detector through the aperture is varied by the wavelength of spectral band. The weld pool size contributing to the spectral band signal varies by the wavelength of the spectral band. The transmittance profile of each spectral band also depends on the focus shift of imaging optics. By processing the measured spectral band signals, the size of a weld pool, the power variation on a workpiece and the focus shift of imaging optics can be monitored simultaneously.

Abstract: The present invention relates to an apparatus for measuring surface relief profile of an object by projecting a line-shaped laser sheet beam in triangulation method and anisotropic magnification optics for improving the measurement resolution. The purpose of the present invention is to provide a system or an apparatus capable of measuring relief profiles with anisotropic magnification optics composed with one or more positive and one or more negative cylindrical lenses, which allows it to obtain magnified images along the direction vertical to the length-wise direction of the image of a line-shaped laser sheet beam for higher resolution in the relief profile measurements along the direction parallel to the length-wise direction of a line-shaped laser sheet beam image to measure the same range of area as the range without anisotropic magnification optics.

Abstract: A method and system is disclosed in which the local variation of an extended radiation source is monitored with single-element detector. The chromatic aberration of the imaging optics induces the different transmittance curves for different wavelengths, and the different shape in the transmittance curve is used as a spatial filter which is multiplied to the chromatic intensity profile of the extended radiation source to detect the local variation in the intensity profile of the extended radiation source. The signal processing of the chromatic signals is implemented to detect the size variation and the environmental effects on the extended radiation source. A fiber is also used for remote operation.

Abstract: A method for generating high peak power pulses in lamp pumped continuous lasers by current mixing is disclosed, in which three kinds of oscillations, i.e., pure continuous wave laser oscillation, pure pulse laser oscillation and mixed laser oscillation of continuous wave and pulse lasers are attained without replacing any internal components of the laser. The current mixing is implemented by combining a high peak pulse current from pulse mode power supply and a DC current from the continuous wave laser power supply directly with isolating diodes, whereby a high peak power pulse equivalent to several scores of times the output of a continuous wave laser is simultaneously obtained.

Abstract: A stable DC power system of high-voltage and good-output performance is provided by adding a 3-phase inverter, whereby modified waveform for an output control is produced and a filter to a conventional DC power system and by bridge-rectifying. The modified sinusoidal wave such as a varied wave whose upper portion ranging from 30.degree. to 150.degree. is flat of a 1/2 cycle of the sinusoidal wave, a modified wave whose portions ranging from 30.degree. to 90.degree. and from 90.degree. to 150.degree. are linear in a 1/2 cycle of the sinusoidal wave and a modified wave whose portions ranging from 30.degree. to 90.degree. and from 210.degree. to 270.degree. are recessed so as to be symmetrical with respect to a line in the whole cycle of the sinusoidal wave are used for reducing ripples of the output voltage after the 3-phase rectification.