Patents Assigned to Massachusetts Institute Technology
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Patent number: 5157296Abstract: A magnetic bearing is provided which may be utilized in a fine position control or movement system. Stability is enhanced by providing separate mechanisms for supporting the weight of a platen or other object being controlled with electromagnets utilized to control or compensate for motion of the platen in N degrees of freedom. The support mechanism is preferably one or more permanent magnets having an air gap with the platen which is greater than the air gap for the electromagnets. The mechanisms for supporting the weight of the platen may be made adjustable so as to support the weight of the platen regardless of any changes in such weight by, for example, adjusting the air gap for the permanent magnet to compensate for weight changes. Resonant vibration is reduced by constructing the platen of a hollowed, cellular structure, for example, a honeycomb structure.Type: GrantFiled: December 20, 1990Date of Patent: October 20, 1992Assignee: Massachusetts Institute of TechnologyInventor: David L. Trumper
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Patent number: 5155895Abstract: A method and apparatus for automatic orientation and assembly are provided. A first plurality of parts are mated with corresponding depressions or other irregularities formed in a pallet by vibrating the pallet and moving the parts thereover. A second plurality of parts are then oriented in a predetermined positional relationship with the first parts, for example matingly engaged therewith, by passing the parts over the pallet which is again vibrated, generally with different vibration parameters. The second parts may matingly engage corresponding irregularities in the first part, may be positioned and oriented by further irregularities on the pallet, or a template may be provided over the pallet with openings for positioning and orienting the second parts. The passing of parts over the pallel and vibration of the pallet may be repeated for additional parts to be assembled if desired.Type: GrantFiled: September 13, 1990Date of Patent: October 20, 1992Assignee: Massachusetts Institute of TechnologyInventors: Mark J. Jakiela, Paul Moncevicz, Karl T. Ulrich
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Patent number: 5155211Abstract: A megakaryocyte stimulatory factor (MSF), purified to homogeneity, is an acidic protein (pI=5.1) with an Mr=15,000 which stimulates PF4-like protein synthesis in rat promegakaryoblast cells by as much as 7-fold, and exhibits half-maximal activity at a concentration of 0.8 pM. MSF exhibits no biologic activity corresponding to other known hemopoietic growth factors, and appears to be specific for the megakaryocyte lineage.In the given examples, MSF was purified to homogeneity (as judged by SDS-PAGE and isoelectric focusing in the presence of 9.2 M urea) from serum-free conditioned medium obtained from cultured human embryonic kidney (HEK) cells, and to near homogeneity from thrombocytopenic plasma.Type: GrantFiled: November 16, 1989Date of Patent: October 13, 1992Assignee: Massachusetts Institute of TechnologyInventor: Robert D. Rosenberg
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Patent number: 5155561Abstract: The base layer of a power permeable base transistor is formed as comb structures with grating teeth of the combs extending into active regions of semiconductor material. Extended active regions are separated by inactive regions over which collector contacts extend. Large devices have digitated base layers. The comb structures are fabricated by sputtering a uniform layer of tungsten and forming a nickel mask over the tungsten by both X-ray and photolithography techniques. The tungsten exposed by the nickel mask is then etched to leave the comb structures.Type: GrantFiled: January 5, 1988Date of Patent: October 13, 1992Assignee: Massachusetts Institute of TechnologyInventors: Carl O. Bozler, Steven Rabe, Mark A. Hollis, Christopher T. Harris, Kirby B. Nichols
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Patent number: 5155357Abstract: A portable mass spectrometer system. The system includes a sample inlet for receiving a sample of analyte molecules and an ion source for producing sample ions by ionization of the sample molecules. A cycloid mass analyzer is provided and adapted to receive the sample ions. The mass analyzer has a means for inducing an electric field in an analysis region and a rear earth permanent magnet material for inducing a static magnetic field in the analysis region, oriented substantially normal to the electric field. A detector is provided for detection of said sample ions in the analysis region. A vacuum means maintains a low pressure in the analysis region. In various embodiments, the system is hand-portable and self-contained, including a 12V rechargeable battery power supply, and a magnet that includes a rare earth permanent magnetic material such as neodymium-iron and samarium-cobalt alloys.Type: GrantFiled: July 23, 1990Date of Patent: October 13, 1992Assignee: Massachusetts Institute of TechnologyInventor: Harold F. Hemond
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Patent number: 5153338Abstract: Optically active derivatives of glycidol are disclosed. These novel compounds, (2S) and (2R) glycidyl m-nitrobenzenesulfonate and (2S) and (2R) glycidyl p-chlorobenzenesulfonate can be readily crystallized to high enantiomeric purity. Their use in other synthesis reactions is also described.Type: GrantFiled: August 3, 1990Date of Patent: October 6, 1992Assignee: Massachusetts Institute of TechnologyInventors: Karl B. Sharpless, Tetsuo H. Onami
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Patent number: 5150374Abstract: An external cavity semiconductor laser comprising a resonance cavity coupled to a diode laser. The cavity may contain a lens or lens system or may be constructed as an optical waveguide. The external cavity may also contain a nonlinear optical material to produce light of a frequency which is higher than that produced by the semiconductor laser. The use of an external cavity insures the single mode and/or single frequency operation of the semiconductor laser.Type: GrantFiled: June 7, 1991Date of Patent: September 22, 1992Assignee: Massachusetts Institute of TechnologyInventor: Aram Mooradian
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Patent number: 5149543Abstract: A method for encapsulating biologically-labile materials such as proteins, liposomes, bacteria and eucaryotic cells within a synthetic polymeric capsule, and the product thereof, are disclosed. The method is based on the use of a water-soluble polymer with charged side chains that are crosslinked with multivalent ions of the opposite charge to form a gel encapsulating biological material, that is optionally further stabilized by interactions with multivalent polyions of the same charge as those used to form the gel. In the preferred embodiment, hydrolytically stable polyphosphazenes are formed of monomers having carboxylic acid side groups that are crosslinked by divalent or trivalent cations such as Ca.sup.2+ or Al.sup.3+, then stabilized with a polycation such as poly-L-lysine. A variety of different compositions can be formed from the crosslinked polymer.Type: GrantFiled: October 5, 1990Date of Patent: September 22, 1992Assignees: Massachusetts Institute of Technology, Pennsylvania Research CorporationInventors: Smadar Cohen, Carmen Bano, Karyn B. Visscher, Marie Chow, Harry R. Allcock, Robert S. Langer
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Patent number: 5148497Abstract: An image interpolator for converting an original image into an enhanced image, the interpolator including rule logic for embodying a rule specifying how pixel patterns associated with first subband image data transform into corresponding pixel patterns associated with second subband image data, the first and second subband image data being derived from a reference image; and conversion logic for generating the enhanced image from the original image based upon the rule.Type: GrantFiled: October 10, 1991Date of Patent: September 15, 1992Assignee: Massachusetts Institute of TechnologyInventors: Alex P. Pentland, Eero P. Simoncelli, Thomas P. Stephenson
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Patent number: 5146926Abstract: An array of electrodes is applied to an internal or external surface of a biological system such as a human being. The electrodes generate signals which are processed to compute a surface differential of the surface potential at a multiplicity of spatial locations within a given time epoch. The signal processing is repeated for multiple sequential time epochs and an image is constructed from the surface differential of the surface potential for each time epoch. Thereafter, the sequential images corresponding to sequential time epochs are displayed. The two-dimensional image changes as the distribution of bioelectric sources evolves so as to provide a motion picture of electrical activity.Type: GrantFiled: October 26, 1990Date of Patent: September 15, 1992Assignee: Massachusetts Institute of TechnologyInventor: Richard J. Cohen
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Patent number: 5146033Abstract: The invention pertains to rhenium (VII) compounds which are catalysts for metathesis of ordinary olefins (hydrocarbons) and functionalized olefins in a homogeneous phase and to methods of synthesizing these compounds. The rhenium compounds comprise a rhenium (VII) atom centrally linked to an alkylidene ligand, an alkylidyne ligand, and two other ligands of which at least one ligand is sufficiently electron withdrawing to render the rhenium atom significantly active for metathesis.Type: GrantFiled: December 19, 1991Date of Patent: September 8, 1992Assignee: Massachusetts Institute of TechnologyInventors: Richard R. Schrock, Robert Toreki
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Patent number: 5144549Abstract: A time delay control system in which estimated unknown dynamics of a controlled process are caluclated using calculations representative of convolutions of a state transition matrix with past data. A user or high level controller provides desired dynamics for a process. Periodic measurements of the processor taken to determine an error vector between the desired dynamics and the actual state of the process. The desired dynamics are used to determine the desired effects based on the present measured value of the state variables. The desired effects and the estimated effects of unknown dynamics are combined and multiplied by a pseudo inverse of a control matrix to obtain a control value. An error vector is multiplied by a feedback gain matrix and added to the control value to produce signal inputs to the process.Type: GrantFiled: June 29, 1990Date of Patent: September 1, 1992Assignee: Massachusetts Institute of TechnologyInventor: Kamal Youcef-Toumi
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Patent number: 5144629Abstract: This invention relates to a method and apparatus for tuning a laser amplifier, which amplifier utilizes a laser medium capable of lasing over a selected broad wavelength band. The lasing medium is pumped and a selectively tunable optical parametric generator (OPG), such as an optical parametric amplifier or an optical parametric oscillator, is driven with an optical signal at a wavelength such that the OPG, as tuned, generates an output at a selected wavelength within the broad wavelength band of the lasing medium. The output from the OPG is injected as a seeding input to the lasing medium to adjust the lasing wavelength thereof. All components of the system are preferably solid state components and the OPG is preferably driven from the pumping source so as to assure proper synchronization.Type: GrantFiled: April 30, 1991Date of Patent: September 1, 1992Assignee: Massachusetts Institute of TechnologyInventor: Santanu Basu
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Patent number: 5143670Abstract: Thermally and acoustically insulating, water-repellent, fire resistant, slab-shaped building components are formed by wetting a plurality of expanded polystyrene beads with water and water-soluble synthetic resin, to coat the beads adding an inert filler drying and/or polymerizing the resin and mixing the thus-coated beads with predetermined proportions of cement, sand, fluidifying additive and water and also stearate. The thus-obtained mixture is put into a slab-shaped form and reinforcing components are immersed in the form. The mixture is cured and a thus-formed slab-shaped element is withdrawn from the form.Type: GrantFiled: July 19, 1989Date of Patent: September 1, 1992Assignee: Massachusetts Institute of TechnologyInventor: Ferdinando De Buzzaccarini
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Patent number: 5142385Abstract: First and second coherent beams illuminate a common area on an exposure station. A phase detector senses the relative phase between the first and second beams to provide a control signal. There is at least one phase shifter in the path of at least one of the coherent beams. The control signal is coupled to the phase shifter to adjust the phase imparted thereby so that the relative phase between the first and second coherent beams is substantially constant.Type: GrantFiled: January 9, 1991Date of Patent: August 25, 1992Assignee: Massachusetts Institute of TechnologyInventors: Erik H. Anderson, Henry I. Smith, Mark L. Schattenburg
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Patent number: 5142073Abstract: Molybdenum and tungsten complexes useful as precursors for catalysts useful in the metathesis of olefins are disclosed. New compounds have the formula: M(R.sub.1).sub.2 (NR.sub.2).sub.2 (R.sub.3).sub.x.Type: GrantFiled: April 30, 1991Date of Patent: August 25, 1992Assignee: Massachusetts Institute of TechnologyInventors: Richard R. Schrock, Harold H. Fox, Brian L. Goodall
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Patent number: 5139606Abstract: A method of etching the surface of a substrate in a closed environment including the steps of contacting the surface of the substrate with a molecular chlorine etching gas, allowing a passivation layer to form on the surface of the substrate with atomic layer precision, and photochemically removing at least a portion of the passivation layer by irradiating the portion without destruction of the layer of material immediately underlying the passivation layer.Type: GrantFiled: July 10, 1990Date of Patent: August 18, 1992Assignee: Massachusetts Institute of TechnologyInventor: Paul A. Maki
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Patent number: 5139925Abstract: A resist exposed to patterned radiation at 193 nm forms a highly crosslinked barrier layer in the exposed regions of the resist surface. The complementary surface regions are silylated in a silicon-containing reagent, and the exposed regions are readily removed by a oxygen RIE plasma. The laser exposure is a reciprocal process allowing precise control. Pattern definition is enhanced by limiting the exposure and the silylation to the surface of the resist.Type: GrantFiled: October 18, 1989Date of Patent: August 18, 1992Assignee: Massachusetts Institute of TechnologyInventor: Mark A. Hartney
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Patent number: 5136169Abstract: A method of monitoring the travel of a beam of energy on a substrate having a fiducial pattern rigidly fixed relative to the substrate, the pattern embracing an area where the beam can create a useful image with submicron precision. The method includes: adjusting the beam such that the dose delivered by the beam is sufficiently high to generate a signal produced by the interaction of the beam and the fiducial pattern, the signal being representative of the relative position of the fiducial pattern and the travel, the dose being sufficiently low so that the area of the substrate over which the beam passes remains receptive to subsequent creation, with submicron precision, of a useful image; moving the beam across the substrate; detecting the signal produced by the interaction of the beam with the fiducial pattern; and comparing the detected signal with a predetermined signal to provide a position signal representative of the beam travel with submicron precision.Type: GrantFiled: April 5, 1991Date of Patent: August 4, 1992Assignee: Massachusetts Institute of TechnologyInventors: Henry I. Smith, Erik H. Anderson, Mark L. Schattenburg
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Patent number: 5134414Abstract: A method and apparatus for suppressing leakage spikes in a radar duplexer. A flash of radiant energy is triggered immediately prior to sending a radar pulse so as to ionize the gases in a duplexer tube before the leading edge of the radar pulse reaches the tube. The spike suppressor includes an radiant energy source which attaches to the radar duplexer so that the source shines into the duplexer tube. A pulse generator is provided for activating the source in response to a trigger signal.Type: GrantFiled: March 20, 1991Date of Patent: July 28, 1992Assignee: Massachusetts Institute of TechnologyInventors: Joseph G. Ditullio, Peter D. Dolan, Edward H. Shively, William R. Romaine