Abstract: Acoustic windows that are portions of an ultrasonic sensor used to measure a rate of flow of a fluid are wetted whenever the fluid is present. These windows may become coated with a contaminant film during operation. The contaminant may be removed by applying an acoustic cleaning signal to the same ultrasonic transducers used in the flow measurement. The cleaning signal frequency is commonly on the order of one to a few tens of kilohertz, which is substantially less than the measurement signal frequency, which is commonly on the order of a few megahertz. Several approaches are described that isolate the cleaning and measurement functions and that provide protection to signal amplifiers that are used in the measurement process and that could be damaged by high cleaning voltages.

Abstract: Tangential forces present at the mating area between a clamp-on transducer and a pipe can be made very small in order to provide a higher quality, more stable acoustic coupling. In some cases this is accomplished by providing a low friction bearing on a surface of a transducer housing. This bearing may be a slippery surface portion, or may involve a rotary bearing mounted on the housing. In other cases, where a steel pipe is used, pairs of permanent magnets coupled by a yoke can provide the desired clamping force directed solely along a radius of the pipe.

Abstract: An in-line magnetic flow meter has an electrically insulated quasi-annular voltage sensing path defined between an internal wall of a meter body and an outer wall of an axially disposed hollow tube. Although less than 100% of the fluid flow passes through the sensing region, the choice of an inner tube reduces flow impedance introduced by the meter, when compared to other meters providing a quasi-annular sensing path. In addition, by forming two electromagnet coils on a single core and using axially separated pairs of electrodes, the present arrangement allows one to provide two flow meters in the space normally occupied by one.

Abstract: A time-of-flight flow meter that is particularly useful for measuring the flow of gases, such as steam, uses a spark gap periodically energized with an electrical pulse to generate an acoustic pulse. The pulse is detected by upstream and downstream acoustic detectors that may be capacitive transducers having flexible plates wetted on both sides by the fluid so that no external venting is required. The acoustic detectors may be electrically heated to avoid condensation effects. In some cases the interior of the pipe or other conduit is shaped near the source so as to define acoustic beams aimed at the detectors and so as to concentrate the received acoustic energy on the detectors.

Abstract: The polarization of a beam of radiation can be changed by passing the beam through an electrochromic device (ECD) and applying voltages to the ECD to selectively change the absorption of components of the beam and to change its polarization. This method can operate over a wide spectral region that may extend from 200 nm to 30 ?m. In addition, the polarizer can be configured to be tuned by moving the polarizer transversely with respect to a beam of radiation that is characterized by a selected wavelength. In this case either or both of the composition and thickness of the polarizer may vary along the direction of motion in a controlled fashion.

Abstract: A magnetic flow meter has an electrically insulating member extending inward from an inner wall of a flow tube and extending along a selected axial portion of the tube. At least one pair of electrodes are placed adjacent opposite sides of the insulating member at a selected axial position so as to define a voltage sensing path. At least one of the electrodes is connected to an adjustment mechanism that allows the electrode to be set at a selected radial position, where the position can be selected so that the sensed voltage varies linearly with volumetric flow rate.

Abstract: A solid-state electronic electrochromic device (ECD) operates electronically rather than relying on the ionic motion that is common in electrochromic devices. The electronic ECD has at least one active layer sandwiched between two electrodes. The active layer is made of mixed metal oxides and may be made of a mixture of tungsten and praseodymium oxides. The electronic ECD may have only a single active layer, or may have multiple layers that have the same composition and that are separated by thin transparent metal films. Some versions of the electronic ECD incorporate a distribution of small metal particles within the active layer.

Abstract: A magnetic flow meter employs resonant circuit principles to increase the strength of the magnetic field to produce larger electrode difference potentials so that environmental influences have less effect on the operation of the flow meter. The flow meter may use an electromagnet that is resonant with a capacitor, generally at a frequency on the order of ten kHz. In addition, the meter comprises a magnetic field sensor and timing circuits that can sample the electrode difference potentials when the field is at a maximum and the time rate of change of field is instantaneously zero. Some versions of the meter operate in a one-shot mode and others operate with a burst of drive pulses.

Abstract: The flow responsive voltages detected at the electrodes of magnetic flow meters are typically reduced in magnitude by an electrical impedance shunting effect of the fluid on the electrodes. This problem is resolved by providing buffering electrodes located near, and preferably both upstream and downstream, of flow responsive sensing electrodes. The buffering electrodes are driven by amplifiers having signals detected by the flow responsive electrodes as an input. Thus, fluid in the vicinity of the flow responsive electrodes is forced to acquire an offset voltage which can reduce the shunting effect to a negligible level.

Abstract: A transit-time flow sensor determines a rate at which fluid flows by measuring a propagation time difference between upstream and downstream acoustic transmissions. This may involve providing an acoustic path consisting of sequentially traversed path segments and a repeating arrangement that uses the energy in a received pulse to repeat the pulse in the next sequential segment.

Abstract: Problems of instability and non-linearity in probe-type magnetic flow meters are ameliorated by either or both of a conductor coating connecting a tip portion of the probe with a supporting probe stem and either a shrouding arrangement or skewed end plates parallel to the flow direction that are arranged adjacent to the sensing electrodes and that act to straighten and confine fluid flowing past the electrodes.

Abstract: An electrically conductive multilayer thin film structure and composition is transparent in both the visible and infrared portions of the spectrum. This multilayer film is readily deposited on a variety of substrates, including plastics, and survives such in service conditions as flexing, vibration, thermal cycling, thermal shock, ultraviolet exposure, and high humidity. The preferred films are also compatible with conventional photolithography processes.

Abstract: A support apparatus for a café umbrella has a support arm pivotally attached to a generally vertical pole. In a preferred uneven-arm arrangement, a canopy-supporting end of the arm is further to one side of the pole than a second, actuator-connected end of the arm is to the other side of the pole. An actuator mechanism connected between the pole and the shorter portion of the arm and can be used to raise or lower the canopy supporting end of the arm by moving the second end of the arm respectively toward or away from the pole. A cable assembly runs along the length of the support arm so that one end hangs beneath the canopy supporting end of the arm where it can retain a removable canopy. The other end of the cable assembly is attached to the pole so that when the actuator draws the arm toward the pole and raises its canopy-supporting end, the free end of the cable moves downward so as to collapse the canopy.

Abstract: A capacitive sensor for detecting the presence of an object adjacent a panel is described. The sensor comprises an electrically conducting sensor element coupled to a capacitance measurement circuit. In use, the capacitive sensor is mounted with the sensor element adjacent an underside of the panel. The sensor element includes a flared portion which deforms when pressed against the panel to provide an extended contact area between the sensor element and the panel. When a user touches an upper side of the panel above the extended contact area, the capacitance of the sensor element is modified. This is detected by the measurement circuit and identifies a touch.

Abstract: A step assembly for use with a truck load bed has an elongated support member that can be inserted into a hitch receiver. The support is pivotally connected to a step that can be moved into several positions. In a rearward position the step is far enough to the rear of the body of the truck that the step may be stood upon when the tailgate of the vehicle is in an open, lowered position. This allows someone carrying something that is to be loaded onto the truck to approach the truck directly from the rear, to step onto the step and then onto the lowered tailgate. In an alternate, lateral, position the step is adjacent one of the sides of the load box. This allows someone to stand on the step member and reach into the load box to deposit or retrieve some relatively small article when the tailgate is in a raised, closed position. The linkages are constrained to keep a long side of the step perpendicular to the centerline of the truck in both the rearward and lateral positions.

Abstract: Combining a plurality of local flow measurements made at more than one location to generate a composite flow value can improve the accuracy of the overall measurement. The reliability and long term accuracy of a multi-sensor flow measurement are improved by a two-step process. During an initial learning period, when all of the local sensors are providing accurate local measurements, a calibration table is built up that associates each calculated composite flow value with the set of local flow signal values from which it was calculated. In a subsequent operational period each time the composite flow rate is to be determined the flow meter apparatus first checks to see if all the local sensors are working properly and, if one of them is not working properly, its output is replaced with the corresponding value from the calibration table.

Abstract: The present invention describes a system and method for using agent-based distributed reasoning to manage a computer network. In particular, the system includes interface agents to integrate event streams, distributed reasoning agents, and response agents, which run on hosts in the network. An interface agent monitors a resource in the network and reports an event to an appropriate distributed reasoning agent. The distributed reasoning agent, using one or more knowledge bases, determines a response to the event. An appropriate response agent implements the response. Characteristics of the reasoning agent's mean that they can work together collaboratively, as well as implementing parallel algorithms.

Abstract: Walls and other structures can be made from blocks assembled from relatively light-weight standard panels that fit together like a puzzle. The blocks are held together without the use of mortar. Each block is formed of six rectangular panels fitted together by sliding capturable elements into cooperating receiving grooves. All of the panels have a common thickness and each panel has two parallel faces. Three types of panels are involved in making the block.

Abstract: Problems of instability and non-linearity in probe-type magnetic flow meters are ameliorated by either or both of a conductor coating connecting a tip portion of the probe with a supporting probe stem and flat end plates parallel to the flow direction that are arranged adjacent to the sensing electrodes and that act to straighten and confine fluid flowing past the electrodes.

Abstract: A wrap dispensing apparatus for wrapping an article with wrapping material includes a base; a hub assembly; a threaded spindle mounted to the base and the hub assembly, and a brake assembly to control the movement of the threaded spindle. The threaded spindle supports a roll of material between the base and the hub assembly. Further included is a steering arm that is attached to the base and the hub assembly and spaced from the threaded spindle. The base has wheels for omni-directional movement along a horizontal surface.