摘要:
An electronic document delivery system and method in which a broadcast center (150) periodically sends a "catalog" of available documents to a receiving computer (110), thereby allowing a user to browse through the available documents without having to access the broadcast center (150). The documents are transmitted as packets, and the packets are decrypted as soon as they are received, eliminating the need to store both an encrypted and a decrypted version of the documents at the receiving computer. The receiving computer (110) periodically receives information allowing it to decrypt received documents and to encrypt billing information for the receiving computer. The invention is not limited to text-only documents, and can receive all types of documents, such as software, images, text, and full-motion video.
摘要:
A dielectric material is formed into a structure having two parallel broad surfaces with one or more raised integral portions extending transversely across at least one of the broad surfaces. The exterior is uniformly conductively coated resulting in a parallel plate waveguide having a continuous transverse stub element disposed adjacent one plate thereof. Purely reactive elements are formed by leaving the conductive coating on the terminus of the stub element, or by narrowing the terminus of the stub element. Radiating elements are formed when stub elements of moderate height are opened to free space. Radiating, coupling and/or reactive continuous transverse stub elements may be combined in a common parallel plate structure in order to form a variety of microwave, millimeter wave and quasi-optical component including integrated filters, couplers and antenna arrays. Fabrication of the dielectrically-loaded continuous transverse stub element can be efficiently accomplished by machining, extruding or molding the dielectric structure, followed by uniform conductive plating in order to form the parallel plate transmission line. In the case of antenna applications, machining or grinding is performed on the stub terminus to expose the dielectric material at the end of the stub element.
摘要:
Surface-emitting distributed feedback (SEDFB) lasers (10) having a curved grating (30) with a shape that produces good beam quality. A preferred shape is one for which the grating curves away from the center of the gain region (31) of the laser (10). The use of the curved grating (30) of the present invention produces good beam quality from broad area SEDFB lasers with high power and high efficiency. The present invention overcomes self-induced filament formation and dynamic instabilities that limit achievable beam quality. The present invention provides for a holographic method for fabricating curved gratings (31) for the SEDFB lasers (10) that is consistent with laser batch processing.
摘要:
Disclosed is a computer system and a method for the protected distribution of certificate and keying material between a certification authority and at least one entity in the certification authority's domain, comprising the steps of sending keying material, including a password, generated by the Certifying Authority to the entity via a secure medium; generating and protecting, by the entity, a public and a private key pair using the keying material provided it by the certifying authority; generating, protecting and sending a request for a certificate to the certifying authority using the keying material provided it by the certifying authority; requesting, by the certifying authority, that the public key and address of the entity be sent to the certifying authority; protecting and sending the public key and address of the entity to the certifying authority using the keying material provided it by the certifying authority; assembling and issuing the certificate to the entity from the certifying authority and recording the public key of the entity at the certifying authority for public use within the domain of the certifying authority.
摘要:
A spacecraft power bus regulation method and apparatus for a spacecraft. The spacecraft has solar arrays (10) and a battery (30) coupled to the spacecraft power bus (32) to drive electrical loads (34). A bus voltage limiter (38) controls the flow of current from the solar arrays while a bidirectional battery controller (36) controls power flow into and out of the battery. A processor (46) monitors current flow and battery condition using sensors (40, 42, 44, 48) and controls the bus voltage limiter accordingly. Auxiliary control is provided by the solar array drive (24) which controls the orientation of the solar arrays with respect to the sun.
摘要:
A shrouded pin electrode structure including an elongated pin that extends into the volume of a gas containment structure of an RF excited gas discharge light source and is physically isolated from the discharge gas contained in the volume of the gas containment structure by a shroud structure comprised for example of a gas impermeable dielectric coating or closed end tube.
摘要:
A simplified procedural user interface ("PUI") for controlling the operation of a computer (300), defined in terms of the steps or procedures required to do a given operation. The PUI acts as a graphical checklist that indicates to the user what has to be done and then controls the operation of the computer required to implement the operation. The PUI provides a linked icon representation of a user's task in a series of hierarchical panels (50). The linked icons (58, 60, 62) indicate the steps a user must go through to complete a task using the computer. The hierarchical panels on which the icons reside provide a means to logically group related task steps. The underlying concept is to simplify the computer operation by only presenting the capability required to do a particular task at a given time.
摘要:
A new class of asymmetrical diphenyl-diacetylene liquid crystal compounds exhibit ideal properties for formulating eutectic mixtures suitable for infrared and microwave applications. The new class of liquid crystal compounds comprise asymmetrical nonpolar end groups. These compounds exhibit low melting points, wide nematic temperature range and low heat fusion enthalpy. Eutectic mixtures containing entirely diphenyl-diacetylene homologs using the new compounds have high birefringence, low viscosity and wide nematic range. These unique properties are especially advantageous when these mixtures are used in infrared spatial light modulators, high speed liquid crystal modulators and polymer dispersed liquid crystals shutters. The new asymmetrical diphenyl-diacetylene liquid crystal compounds comprise the following basic structure: R1-C6H4-C=C-C=C-C6H4-R2 wherein R1 and R2 are nonpolar end groups and R1 does not equal R2. R1 is selected from the group consisting of alkyl, alkoxy, alkenyl and alkenyloxy end groups and R2 is selected from the group consisting of alkyl, alkenyl and alkenyloxy. In another embodiment, the liquid crystal compound can comprise an alkenyl group having the general formula: CxH2x+1CH=CH-(CH2)n-2-x in either the R1 or R2 location. Moreover, the liquid crystal compound can comprise such an alkenyl group in both R1 and R2 locations, so long as R1 does not equal R2. Eutectic mixtures for infrared and microwave applications comprise at least one asymmetrical nonpolar diphenyl diacetylene liquid crystal compound having the general structures described above.
摘要:
A visual display device (10) is especially suited for use as a center-high-mounted stop-light (CHMSL) for an automobile rear window which slants downwardly from the horizontal by a small angle. The device (10) includes a linear light source (12) which preferably emits red light. A display panel (14) has a light receiving edge (14a) extending parallel and adjacent to the light source (12) and first and second opposing surfaces (14b, 14c). The second surface (14b) slants toward the first surface (14c) in a direction away from the edge (14a) and is formed with steps (14d) having walls (14e) which are angled toward the edge (14a) such that the peak output light propagating through the display panel (14) from the edge (14a) is refracted horizontally out of the panel (14). The walls (14e) of the steps (14d) are formed with laterally spaced depressions (14f) for lateral dispersion of light. In addition to use as a CHMSL, the display device (10) can be employed in other applications in which a uniform, linear light source is required.
摘要:
An interactive training system (10) for simulating an operating environment. The system (10) can operate in both freeplay and procedural modes. The system (10) includes a plurality of simulated displays (18) simulating actual displays in the operating environment. The simulated displays (18) indicate the state of various components of the operating environment to the user. A plurality of manipulable input devices (20) permits the user to interact with the training system (10). Simulation software (22) responds to the input devices (20) and controls the displays in response thereto. Procedure monitoring software (26) determines the status of the input devices as a result of the user's manipulation of the input devices. Condition monitoring software (24) monitors conditions within the procedure monitor (26) and simulation software (22). These conditions may occur directly or indirectly as a result of the manipulation of the input devices (18) by the user. This system (10) simplifies the monitoring of complex user actions.