摘要:
Acoustic weight or mass sensing technology (referred to here as Acoustic Weigh In Motion (AWIN)) provides accurate weighing of any type of moving load moving over a load bearing medium. Acoustic transducers are affixed to or embedded in the load bearing medium. One or more source acoustic transducers propagate an acoustic wave over an acoustic path through the medium between the source and receiver transducers when the medium is in an unloaded state. The wave is detected at one or more receiving acoustic transducers. A propagation time delay is determined for the unloaded state. When a moving load travels over the acoustic path in the medium, the acoustic propagation time delay for that loaded state is determined. The difference between the acoustic propagation time delays for the unloaded and loaded states is determined. That acoustic propagation time delay difference is used to determine the weight or mass of the moving load.
摘要:
A method of measuring bone strength under dynamic loading is provided using an ultrasonic probe wave sensor to sense a low-frequency pump wave and an ultrasonic probe wave implemented to the bone. The bone is cyclically loaded with compressional and rarefactional pump waves, and probed with the probe wave that is timed according to the pump wave to determine the wave velocity of the probe wave. Bone strength is interpreted by measuring wave velocity changes during the pump wave cycles. Ultrasonic velocity derivatives are used to determine bone third-order (nonlinear) elastic constants that are linked to bone strength. High-resolution second-order (linear) elastic constants are provided through measurement of absolute phase velocity. A pulsed phase lock loop is locked at intervals as the probe wave phase is modulated over 360 degrees providing probe wave harmonic numbers that are correlated with the pump wave frequency to determine the probe wave velocity.
摘要:
A bond strength tester and method for determining certain bond strength parameters of a bonded component, including a phaselocker, a transducer, a loading device that is capable of applying stress-loads to the bond, a controller for controlling the loading device, a data recording device to acquire data, and a computer device to analyze data calculating certain bond strength parameters.
摘要:
An acoustic energy-based, non-contact or contact testing approach provides low cost, highly accurate, and reliable information to (a) identify flaws and anomalies and (b) assess the integrity of a particular material. This approach is not hindered by surface conditions or impediments, and indeed, looks beneath the surface of the material by propagating an acoustic wave through the material using two differential transducers. A dynamic differential measurement is made of the material under a load condition and an unloaded condition that allows identification and assessment of various characteristics of the material. Multiple “windows” of information may be generated that permit (a) direct detection of flaws, defects, and anomalies using a scattering technique, (b) detection of crack closure and opening used to assess the stability of the material, (c) determination of strain on the material which relates to its performance, and (d) determination of defect dynamics linked to the defect size and stability.
摘要:
A method, system, and computer-readable media are provided for adjusting one or more video parameters of a video communication session based on a type of use for the video communication session. At least one method includes detecting a use for a certain video communication session and applying a profile of video parameters to the session based on the use. The method further includes detecting a network constraint and adjusting one or more of the video parameters based on the network constraint.
摘要:
Catalyst systems of the Ziegler-Natta type comprise as active constituents a) a solid component comprising a compound of titanium or vanadium, a compound of magnesium, a particulate inorganic oxide as support and an internal electron donor compound, and as cocatalyst b) an aluminum compound and c) if desired, a further, external electron donor compound, wherein the particulate, inorganic oxide used has a specific surface area of from 350 to 1000 m2/g and a mean particle diameter {overscore (D)} in the range from 5 to 60 &mgr;m and comprises particles which are composed of primary particles having a mean particle diameter {overscore (d)} in the range from 1 to 10 &mgr;m and contain voids or channels between the primary particles, where the macroscopic proportion of voids or channels having a diameter of greater than 1 &mgr;m in the particles of the inorganic oxides is in the range from 5 to 30% by volume and the molar ratio of the compound of magnesium to the particulate, inorganic oxide is from 0.5:1 to 2.0:1.
摘要:
Vinyl monomers are polymerized in the aqueous phase in the presence of at least one N-oxyl compound of a secondary amine, having no hydrogen atoms bonded to the &agr; carbon atoms. This process substantially eliminates deposits on reactor surfaces.
摘要:
A method for evaluating changes in the intensity of polychromatic radiation that is transmitted by a source having a known frequency spectrum (e.g. an X-band spectrum), and received by a sensor after having passed through a certain thickness of a body or sample consisting of one or more phases having a known composition, whereby artifact-related reconstruction errors may be corrected. The method is characterized in that the changes in intensity are evaluated by modeling the influences of a number of predetermined parameters related to the nature of each phase on the absorption coefficient of the body in one or more spectral bands of the polychromatic radiation. The method is useful for the tomographic analysis of geological samples or the human body.
摘要:
A data transfer mechanism for a serial interface is provided whereby data transfer may be precisely controlled, eliminating the need for significant buffering. The data transfer mechanism also provides for flexible data transfer in either a byte mode or a burst mode so as to accommodate any of various telecommunications devices having a range of capabilities and data rates, and minimizes host involvement in the data transfer operation.
摘要:
A computer having multiple modules connected by a backplane bus includes multiple competition signal lines and multiple class signal lines. Access to the backplane bus to engage in one or more of multiple types of bus transactions is arbitrated between the modules by classifying the bus transactions into different classes and, during each of a succession of competition cycles, when a module wants access to the backplane bus to engage in a particular type of bus transaction, asserting a class signal line corresponding to a class in which the particular type of bus transaction has been classified. Based on information presented on the class signal lines, it is determined which modules are or are not eligible to compete for access to the backplane bus. When a module is eligible to compete for access to the backplane bus, it drives an identification code associated with the module on the competition signal lines. Then, based on information presented on the competition signal lines, a module is granted access to the backplane bus.