Abstract: An improved test structure for measurement of width of conductive lines formed on substrates as performed in semiconductor fabrication, and an improved reference grid for calibrating instruments for such measurements, is formed from a monocrystalline starting material, having an insulative layer formed beneath its surface by ion implantation or the equivalent, leaving a monocrystalline layer on the surface. The monocrystalline surface layer is then processed by preferential etching to accurately define components of the test structure. The substrate can be removed from the rear side of the insulative layer to form a transparent window, such that the test structure can be inspected by transmissive-optical techniques. Measurements made using electrical and optical techniques can be correlated with other measurements, including measurements made using scanning probe microscopy.

Abstract: A test structure for submicrometer metrology as used in integrated circuit manufacture comprises a bridge conductor divided into three segments by pairs of voltage taps. A first segment has no intermediate taps; a second segment has a number of dummy taps intermediate its ends; and a third segment has a single central tap, which may typically be formed in a different step than the remainder of the test structure, intermediate its ends. Preferably, the central tap extends from the same side of the bridge conductor as the taps at the ends of the third segment thereof. In order to evaluate a manufacturing operation, for example, to monitor the accuracy of registration of successive manufacturing steps, test signals are applied successively between the pairs of pads.

Abstract: A highly rigid structure is provided using six struts connected at three er and three lower nodes to upper and lower support structures. The joint assemblies are formed by half-spherical balls attached to the ends of each of the struts, and retained within cylindrical apertures, such that the center lines of the struts intersect at the nodes. Bending loads on the struts are thus eliminated, while the design and construction of the structure is substantially simplified.

Abstract: An articulated ultrasonic probe for endoscopic examination comprises a transducer head, for example, having one or more rows of independently actuable transducer elements extending along the surface of the probe, parallel to the axis thereof. The probe comprises an articulable section while the transducer head is journaled for rotation with respect to the tip of the probe. In use the tip of the probe is juxtaposed to a structure to be examined; the articulated section of the probe and the rotation of the transducer are controlled separately, such that the transducer elements can be juxtaposed to the structure to be examined. A series of angularly-spaced images may be formed by rotation of the transducer about its axis after articulation of the probe.

Abstract: An improved load compensator for a spring counter-weighting mechanism including a snail cam to provide a constant counter-weight force is described. The cam provides a constant torque to a drum on which are wound cables for exerting a constant counter-weighting force. A manually operable device for altering the relative radial positions of the cam and drum varies the amount of the constant counter-weighting force. The cam is rotated with respect to the drum by a spur gear fitting within a ring gear fixed to the drum and rotated by a knob connected to an axle carrying a pinion gear engaging the spur gear. The spiral surface can be effectively reconfigured with respect to a portion of the cable fitting therearound.

Abstract: An apparatus for removal of organic materials from water includes a reactor for photocatalytic oxidation and/or ionization of organics in the water stream and an ion exchange column for removal of CO.sub.2, dissolved acids, and ionized organics formed in the reactor from the water stream. The reactor includes an elongated flow chamber having an inlet at one end and an outlet at the opposite end. A photocatalytic material is provided as a surface layer on a number of solid members in the chamber, typically a number of rods extending generally parallel to the axis of the flow chamber. The catalyst may be TiO.sub.2 formed by oxidizing the surface of Ti rods. An elongated UV lamp fitting within a tubular quartz window extends along the axis of the reaction chamber. An external circuit connects the electrodes and the water, such that a current flows in the water in the reaction chamber. A potential of up to 600 VDC may be applied between the solid electrodes and water in the chamber.

Abstract: An improved therapeutic device for applying cooling to a body joint to speed healing comprises a reservoir of chilled fluid connected to a container in heat conducting relation with the joint to be chilled by supply and return lines. Fluid is continually recirculated by convection, employing the thermosiphon principle, such that the fluid is recirculated by energy provided by the patient's body heat. Check valves may be provided in one or both of the supply and return lines, preventing reverse flow, and also so that motion of a patient's body joint within the container further motivates the recirculating flow.

Abstract: A compound for the treatment of water polluted by metal ions is obtained by the reaction of potassium or sodium hydroxide in aqueous solution with thiocarbamide and potassium or sodium hyposulfate. After a period of settling, a precipitate forms and is removed; the clear liquid above the precipitate is decanted and used for treating water polluted with metal ions.

Abstract: A connector mechanism for locking together first and second mating connector elements comprises a locking lever geared to rotate a locking rod returned by one of the connector elements. The tip of the locking rod extends into a mating recess in the other of the connector elements. When the rod is rotated, a helical member extending therearound slides along a cooperating arcuate member formed in the recess, locking the two elements together. The actuating rod is rotated by a control lever, enabling one-hand operation of the connector, and providing a readily ascertainable visual indication of the status of the connection. A locking member may be provided for preventing rotation of the lever except when the elements have been correctly assembled to one another.

Abstract: A method and apparatus is described for recognition of hand printed characters using pairs of positive and negative correlative functions (PNCFs), the PNCFs including both pattern and relevance information, implemented by optical elements. A set of optical elements having varying optical density corresponding to a set of two-dimensional PNCFs is generated. A pattern of illumination responsive to the image of the character to be identified is simultaneously transmitted through each of the optical elements implementing the PNCFs. The amount of light transmitted through each of the elements is measured, providing a transmission coefficient. The transmission coefficients are the inputs to a neural network, such that the inputs to the neural network are a set of transmission coefficients resulting from transmission of light corresponding to a character to be identified through a complete set of optical elements implementing a set of PNCFs.

Abstract: An improved method for fabrication of a multiple-element piezoelectric transducer and the transducer produced thereby. A green precursor tape is produced by doctor-blade tape-casting of a slurry containing lead zirconate-titanate (PZT) powder. After drying, individual strips of the tape are stacked between flat plates of previously sintered PZT, and sintered to form PZT strips; Pb from the previously sintered PZT plates makes up any Pb lost from the surfaces of the tape strips during sintering. The PZT strips are stacked interposed by layers of a thermoplastic polymer, and heated to a temperature above the melting point of the polymer, forming a laminate block. This block is then sliced perpendicular to the plane of the layers, forming slabs of alternate PZT and polymer layers; the slabs are then sliced perpendicular to the first slicing planes, forming strips of alternating PZT and polymer material. Electrodes are then added to complete the transducer assembly.

Abstract: An gas metal arc welding (GMAW) process is monitored by disposing a light intensity sensor in the vicinity of the arc, such that the output signal from the sensor is responsive to the intensity of the arc. The arc light intensity is analyzed to determine the arc length, and to determine of the mode of metal transfer and whether the welding process is proceeding as intended.

Abstract: An improved voltage comparator for use in waveform characterization and like applications is disclosed. The current drawn through two matched transistors connected to a source of current is measured to determine whether a reference signal applied to the base of a first reference transistor is greater or less than the signal to be measured applied to the base of the other transistor. Current is only drawn through the two transistors at times corresponding to desired sampling times, substantially eliminating differential heating effects. The comparator provides substantially reduced settling times, resulting in reduced distortion of the waveform.

Abstract: A toy vehicle comprises a chassis having a pair of rear wheels journaled for rotation about a rigid axle and a pair of front wheels mounted for being steered cooperatively. A steering mechanism is controlled by a steering wheel at the end of a steering column connected to the steering mechanism by a universal joint. A child playing with the vehicle can propel the vehicle forward by pushing on the steering wheel, but can only steer it in a desired direction of travel by turning the steering wheel.

Abstract: A composite superconductor having both filamentary and film conductors for carrying the pure and impure components of direct current, respectively, or for alternating current, is disclosed, together with a method of making it, and a preferred arrangement for its use in high power transmission lines.

Abstract: A composite multifilament superconducting structure is provided, which includes an elongated substrate-carrying, longitudinally-directed, sputtered discrete filament of an A-15 type intermetallic superconductor. In a preferable procedure, a plurality of spaced, generally longitudinal grooves are formed on the surface of an elongated filamentary substrate, preferably a metal wire. The walls of the grooves on the substrate surface are shaped to undercut the curvilinear surface of the substrate located between two adjacent grooves so that at least some of the wall portions of the grooves are geometrically shadowed during the subsequent sputtering step in which a superconductor is sputtered onto the substrate. In particular, a film of a suitable superconducting intermetallic compound having A-15 crystalline structure, such as Nb.sub.3 Ge, is thereupon sputtered onto the grooved substrate and deposits at the bottom of the grooves and at the surface portions of the substrate between grooves.