Abstract: A method and apparatus for determining the quality of a multimode laser beam (10). In the preferred embodiment, the apparatus includes a lens (32) for creating a transformed or imaged waist from the input beam. The location of the transformed beam waist and its diameter are then determined. These steps can be carried out by chopping the beam using a rotating hub (34) having apertures (36,38) for selectively passing the beam. Preferably, one of the apertures has a pair of 45.degree. knife edges (40,42). The transmission of the beam past the knife edge is monitored by a detector (30). In operation, the lens focal position is varied while the transmission of the beam past the knife edge is monitored in order to locate and measure the diameter of the transformed waist. The diameter of the beam at one other known location is measured. A processor then calculates beam quality by fitting these measurements to a mathematical model.

Abstract: A passively mode-locked laser (110) is disclosed that includes a resonant cavity (112, 114) having a gain medium (116) therein. A transmissive element (116), which may be the gain medium, is also located in the cavity and is formed from a material which varies the two-dimensional, lateral spatial profile of the beam with respect to intensity due to the Kerr effect. The resonator is arranged such that the round trip gain of the system increases with respect to the intensity of the beam so that mode-locking operation can be achieved. In one approach, the variation in the spatial profile is used to increase the extraction of energy from the gain medium. In another approach, the variation in spatial profile which occurs with an increase inintensity is used to decrease the loss in the system so that pulse operation is favored.

Abstract: Spent nuclear reactor coolant system decontamination solutions are processed to remove the radioactive burden and to separate metallic impurities using ion exchange resins within an electrochemical cell. The application of electric current to the electrochemical cell causes hydrogen ions to replace captured cations held on the ion exchange resin, thereby regenerating the resin for subsequent processing. The displaced cations migrate into the cathode compartment. The radioactive burden and metallic impurities are removed from the cathode compartment of the electrochemical cell. In a particularly preferred process, the cations are plated onto the cathode and disposed of as solids.

Abstract: A method and apparatus for removing a pre-placed prosthetic joint from a bone cavity and conditioning the cavity for receipt of a replacement joint. The pre-placed joint is first pulled from the mantle of hardened cement holding it within the cavity, thus leaving a cavity within the mantle. A mass of fluid cement is then placed within the cement cavity, after which a pulling tool is inserted into the fluid cement and the fluid cement is permitted to cure to bond with the hardened cement and form an integral mass. The pulling tool has detachable sections or sleeves, each with grip forming elements on its exterior and structure to connect a slap-hammer to its proximal end. Tension is then applied to the each section to remove the section and the cement mantle surrounding it from the bone cavity. The process is repeated for each section until all of the cement mantle is removed.

Abstract: The present invention includes a method and apparatus for broadcast distribution of messages and information. Included within the present invention are means for selectively broadcasting messages to specified locales. Further, only the appropriate receiver within that locale operates to receive the message. At the receiver, the message is transmitted to or receivable by the appropriate recipient. In the event that a message is inadvertently lost or transmitted with noise induced errors means are provided for requesting a retransmission of the message.

Abstract: Gabions are constructed of welded wire gridworks comprised of integrally joined planar panels disposed in angle relationship to one another. The gridworks are secured together to define a three-dimensional volume therebetween. In one embodiment the gabions are provided with soil reinforcing mats secured thereto to define a bottom for the three-dimensional volume. The mats extend laterally from the gabions and, when the gabions are assembled in tiers at the face of an earthen formation, serve as soil reinforcements for the formation.

Abstract: An improved tarp fastener is disclosed. The fastener comprises a button and a roughly hair-pin shaped wire retainer, the apical segment is bent out of the plane of the retainer so that the apical segment is spaced sufficiently apart from button to accommodate a variety of tarp thicknesses when the button and retainer are engaged and fastened to a tarp.

Abstract: An apparatus (10) designed to evaluate ion implantation levels in semiconductor samples (42) is disclosed. The device includes an intensity modulated pump laser beam (22) and a probe beam (62) having a different wavelength than the pump beam. The two laser beams are focused on a coincident spot on the surface of the sample. Detectors (80, 96) are provided for measuring the non-modulated reflected power of the pump and probe beams. In addition, the modulated reflected power of the probe beam, that is in phase with the intensity modulated pump beam, is also measured. These three independent measurements are utilized to derive the implant dosage level in the semiconductor sample.

Abstract: In the present invention, an improved retaining member for a disc drive is disclosed. The disc drive has a spindle with a plurality of data storage discs mounted on the spindle. The retaining member is in the shape of a ring with a central hole and a plurality of spaced-apart teeth-shaped members positioned circumferentially about the ring and protruding into the central hole. The retaining member is positioned with the spindle through the central hole and substantially abuts one of the data storage discs. The plurality of teeth-shaped members are urged against the side of the spindle.

Abstract: An apparatus for severing fragments (such as fleurettes) from a one-piece core of an article, such as a cauliflower, as the article is translated between stations along a process path. In a preferred embodiment, the article is translated through a sequence of stations, including a coring station, along the process path. At the coring station, the article is held in a fixed position by an impaling knife or pin, while one or more rotating coring knives are lowered into engagement with the article by a pivoting arm mechanism. The pivoting arm mechanism causes each rotating knife to trace out a generally helical path as it cores the article.

Abstract: There is disclosed a diffractive optical element and a method to produce same wherein the element comprises a base and at least one phase zone comprising an arbitrary multiplicity M of steps of generally identical step height, wherein M is not a power of 2. The method includes the steps of defining a basic depth unit equivalent to a zone height divided by M, defining a depth sequence of N depths wherein N is the smallest integer greater than log.sub.2 M such that each of the M steps can be produced by at least one linear combination of the N depths, defining N masks herein each mask enables the optical element to be processed to one of the N depths and wherein for each mask, the steps to be processed are those which have the one of the N depths in its linear combination and serially utilizing each of the N masks for processing of the optical element.

Abstract: A modified slide catch is disclosed for standard semi-automatic pistols which can be operated by both right-handed and left-handed users.

Abstract: Intrapericardial access is provided by clamping the wall of the pericardium between elongate jaw elements carrying axially aligned tubular guides and passing a guide wire through the guides and the pericardial tissue therebetween. In the preferred embodiment the jaw elements include interengageable ratchets for holding the elements in clamping engagement with the wall of the pericardium and aligned pointed extensions for piercing the pericardial tissue clamped between the elements. Further intrapericardial access is provided by an additional tubular guide carried by the jaw element intended to be disposed in the pericardium during placement of the guide wire.

Abstract: A roof panel attachment system is disclosed herein. The invention includes a roof substrate and a rigid roof panel or a plurality of such panels. The roof substrate is attached to the roof panels and the roof panels are attached to one another utilizing double backed foam adhesive tape.

Abstract: A pattern injector for testing stations in a data communications network and the physical link between them. The pattern injector replaces normal characters in a normal, unmodified stream with injection characters. The pattern injector includes a multiplexor that receives both a current normal character and the injection character as inputs and provides the injection character as its output upon receipt of a select signal. Selection logic responsive to mode selection inputs selectively provides the select signal to the multiplexor in response to the various programmable pattern injector modes. In the Off mode, no replacement of normal characters occurs. In the One-Shot mode, the n.sup.th normal character after detection of a preselected normal character in the unmodified stream is replaced with the injection character. In the Periodic mode, every n.sup.th normal character in the unmodified stream is replaced with the injection character.

Abstract: An audio compression system wherein the compression theshold may be adjusted to a calibrated level. The audio compression system is utilizable in a receiver system whereinan audio input signal received by the receiver system via a communications channel is applied to conditioning circuitry. The conditioning circuitry, in turn, provides a conditioned input signal to an acoustic transducer element for generating a corresponding audio output signal. The audio compression system compares the conditioned input signal and an initial threshold signal to provide a comparator output signal corresponding to the difference between the conditoned input signal and the initial threshold signal. The comparator output signal is provided as a control input to the conditioning circuitry. If the conditioned input signal exceeds the initial threshold signal for a preselected period of time, then the initial threshold signal is switched to a second threshold signal.

Abstract: A method and apparatus for determining the quality of a multimode laser beam (10). In the preferred embodiment, the apparatus includes a lens (32) for creating a transformed or imaged waist from the input beam. The location of the transformed beam waist and its diameter are then determined. These steps can be carried out by chopping the beam using a rotating hub (34) having apertures (36, 38) for seletively passing the beam. Preferably, one of the appertures has a pair of 45.degree. knife edges (40, 42). The transmission of the beam past the knife edge is monitored by a detector (30). In operation, the lens focal position is varied while the transmission of the beam past the knife edge is monitored in order to locate and measure the diameter of the transformed waist. The diameter of the beam at one other known location is measured. A processor then calculates beam quality by fitting these measurements to a mathematical model.

Abstract: An improved real-time confocal scanning microscope, and an improved perforated disk for use in such microscope. A preferred embodiment of the inventive microscope includes a polarizing beamsplitting cube and a rotatable Nipkow disk perforted with a hexagonal hole pattern. The disk is preferably mounted so that the scan lines produced as the disk rotates will cross both the sample feature to be imaged and the sensor array in the system's video camera at an angle substantially equal to 45 degrees. This disk orientation ensures that brightness variations caused by a non-uniform scan will not affect the measurements. Rotation of the disk is preferably synchronized with the camera frame rate to prevent any scan errors from causing random (frame to frame) variations in the camera output. The polarizing beamsplitting cube consists of two triangular prisms connected (i.e., cemented) together by a dielectric film.

Abstract: A disposable portable urinal for males comprising a collapsible cylindrical collar having the perimeter of one end sealably attached to a receptacle for deposit of fluilds therein. The collar has handle tabs attached to its exterior surface to facilitate gripping. An adhesive strip is attached to the exterior of the collar. Score lines located on the surface of the collar allow the collar to be laterally collapsed and longitudinally folded and sealed upon itself.

Abstract: A method and apparatus for verification of personnel identity by correlation of fingerprint images.