Abstract:
A method for subscribing for presence information, wherein: a delegated watcher client or an application server sends a subscription message of a watcher client to a presence server; when determining that the subscription message is a delegated subscription, the presence server processes the message according to delegation authorization rules; when determining that the subscription message is a non-delegated subscription, the presence server processes the message in non-delegated subscription mode; and the presence server saves the subscription relation obtained by processing the message. The present invention further provides a system for subscribing for presence information and a presence server. By employing the present invention, the subscription mode of the presence information may be made more flexible.
Abstract:
A chip-scale packaged IC is made by bonding one or more singulated die chips (from an IC wafer) to a common substrate, such as a single cap wafer (or a portion thereof) and cutting (singulating) the substrate to yield individual, chip-scale packaged ICs. Alternatively, each die chip is bonded to an individual, pre-cut cap. Electrically conductive paths extend through the cap wafer, between wafer contact pads on the surface of the cap and electrical contact points on the IC wafer. Optionally, the cap wafer contains one or more die. The IC wafer can be fabricated according to a different technology than the cap wafer, thereby forming a hybrid chip-scale packaged IC. Optionally, additional “upper-level” cap wafers (with or without die) can be stacked to form a “multi-story” IC.
Abstract:
A collimator includes a pair of first plate members which define an X-ray passing aperture by a spacing between their opposed end faces, a second plate member which is movable in a direction parallel to a moving direction of the first plate members, a pair of third plate members which are movable symmetrically with each other in a direction perpendicular to the moving direction of the first plate member and which define an X-ray passing aperture by a spacing between their opposed end faces, and a fourth plate member which is movable in a direction parallel to the moving direction of the third plate members.
Abstract:
A wafer-level packaged IC is made by attaching a cap wafer to the top of an IC wafer before cutting the IC wafer, i.e. before singulating the plurality of die on the IC wafer. The cap wafer is mechanically attached and electrically connected to the IC wafer, then the die are singulated. Electrically conductive paths extend through the cap wafer, between wafer contact pads on the top surface of the cap and electrical contact points on the IC wafer. Optionally, the cap wafer contains one or more die. The IC wafer can be fabricated according to a different technology than the cap wafer, thereby forming a hybrid wafer-level package. Optionally, additional “upper-level” cap wafers (with or without die) can be stacked to form a “multi-story” IC.
Abstract:
A carbon nanostructure adhesive for adhering two surfaces together, including: an array of vertically aligned carbon nanostructures on a first surface; and a second surface positioned adjacent to the vertically aligned carbon nanostructures such that the vertically aligned carbon nanostructures adhere the first and second surfaces together by van der Waals forces.
Abstract:
Current-mode preamplifiers are provided. In accordance with an embodiment, a current-mode preamplifier includes a transistor, that acts as an input stage for the preamplifier, and a pair of current mirrors. The transistor includes a gate connected to the input of the preamplifier, a source connected to a first voltage supply rail, and a drain. The first current mirror, which is connected to a second voltage supply rail, includes an input connected to the drain of the first transistor, and an output. The second current mirror, which is connected to the first voltage supply rail, includes an input connected to the output of the first current mirror, a first output connected to the input of the preamplifier, and a second output connected to the output of the preamplifier.
Abstract:
A thermal accelerometer device that allows up to three axes of acceleration sensing. The thermal accelerometer includes a substantially planar substrate, a cavity formed in the substrate, a heater element, and at least first and second temperature sensing elements. The heater element is suspended over the cavity, and the first and second temperature sensing elements are disposed along the X or Y axis in the substrate plane on opposite sides of and at equal distances from the heater element. The thermal accelerometer employs differential temperatures detected by the temperature sensing elements to provide indications of acceleration in the X or Y directions. Further, the thermal accelerometer employs a common mode temperature detected by the temperature sensing elements to provide an indication of acceleration along a Z axis perpendicular to the X and Y axes.
Abstract:
A thermal accelerometer device that provides a compensation for sensitivity variations over temperature. The thermal accelerometer includes signal conditioning circuitry operative to receive analog signals representing a differential temperature is indicative of a sensed acceleration. The signal conditioning circuitry includes serially connected A-to-D and D-to-A converters, which implement a temperature dependent function and process the received signals to provide a compensation for sensitivity variations over a range of ambient temperature. To provide a ratiometric compensation for variations in power supply voltage, a buffered voltage proportional to the supply voltage is provided as a reference voltage to the D-to-A converter. The thermal accelerometer includes a self-test circuit for verifying the integrity of a heater, temperature sensors, and circuitry included within the device.
Abstract:
An integrated convective accelerometer device. The device includes a thermal acceleration sensor having a thermopile and a heater element; control circuitry for providing closed-loop control of the thermopile common-mode voltage; an instrumentation amplifier; clock generation circuitry; voltage reference circuitry; a temperature sensor; and, output amplifiers. The device can be operated in an absolute or ratiometric mode. Further, the device is formed in a silicon substrate using standard semiconductor processes and is packaged in a standard integrated circuit package.
Abstract:
An infrared collector employs a concentrator formed of a plurality of spatially related gradient-indexed (GRIN) lenses and a photodetector, interconnected by optical fibers. Since the GRIN lenses are arranged on a hemispherical shell, the concentrator is relatively insensitive to the direction of the incoming infrared radiation. Optical fibers are used to connect the GRIN lenses to a photodetector, whereby assembly is simplified. The infrared detector in the collector of the present invention has a size that is significantly smaller than those used in conventional collectors. The concentrator has high optical gain, and therefore, is particularly well adapted for use in low-power portable systems. The arrangement is useful as a node in an infrared data network.