Abstract: A method for fabricating a silicon diaphragm comprises the steps of preparing an n-type silicon substrate; diffusing n.sup.+ impurities in the silicon substrate to form an n.sup.+ diffusion region in a part of the upper wall thereof; growing an n-type silicon epitaxial layer thereon; forming a through-hole in the n-type silicon epitaxial layer to expose a part of the n.sup.+ diffusion region; performing an anodic reaction in an HF solution to make the n.sup.+ diffusion region a porous silicon layer; etching the porous silicon layer to form an air-gap;and, sealing the through-hole.

Abstract: An interactive image data transmission system uses the expertise of an image end user distant from the image collection point. An image with a wide angle field of view is transmitted to the end user in lossy-compressed form. The image is displayed at the receiving end with errors introduced by the lossy compression. The end user can select and specify a narrowed field of view, and the image capturing parameters are modified as necessary under end user control to capture a desired image of the narrow view field. The transmitting station transmits a lossy compressed version of the narrow view image which is displayed for the user, and the user selects at least one window of definite interest within the image. Then, additional image data sufficient to provide a correct display within the window(s) of interest is transmitted to the receiving station and the display is updated within the window(s). The additional data may be difference data in a variable length diagonal code.

Abstract: A linearized power amplifier is provided which comprises a non-linear radio frequency (RF) power amplifier, a linearization circuit such as a Cartesian Feedback circuit, an RF feedback circuit; an IF feedback circuit; or a feedforward circuit, and a dynamic bias modulation circuit for modulating an operating voltage of the amplifier. The dynamic bias modulation means includes an envelope determining circuit, signal processing circuits in which predetermined data or a simplified transfer function determined from measured characteristics of the amplifier is stored and used to produce power bias and/or base or gate bias signals, and driver circuits for modulating the power supply voltage and/or base or gate bias voltage of the RF amplifier in response to the bias signals. The dynamic bias modulation may be used with a BJT-based, and FET-based or any other type of RF power amplifier.

Abstract: Apparatus and a method using ultrasonic signals to determine the distance between the displacement of two points in space. An ultrasonic distance measurement unit (1) generates frequency modulated ultrasonic waves using binary shift keying. The signals are transmitted by the transmitting transducer (2) towards a reflector assembly (30), preferably comprised of two reflectors (31, 32). One of the reflectors (31) is smaller than the other reflector (32), and the smaller reflector (31) is positioned in front of the larger reflector (32). The reflected signals are received by the receiving transducer (3). The unit (1) phase digitizes and processes the received signal by recording time stamps of zero-crossings of the received signal. The speed of sound may be determined by a temperature measurement system (5) and/or by measuring the transit time difference between the two reflectors (31, 32) of the assembly (30).

Abstract: An electronic circuit or device is protected from tamper and/or theft of data contained therein by encapsulation in a hosing and a polymer cradle. The cradle comprises a transducer capable of generating a voltage, detection means to detect said voltage, and protection means associated therewith to destroy and/or alter said circuit, device and/or information and/or record said voltage, characterized in that said transducer is a polymeric pressure/voltage and/or temperature/voltage transducer associated with said detection means such that on alteration of pressure or temperature applied to said transducer beyond pre-set limits, said voltage is sensed by said detection means thereby activating said protection means.

Abstract: A finishing gear hob whose shape is of a worm includes a working side with cutting edges K, which are in the form of a continuous equally-rising spaced cylindrical helix, and edges K are formed by the intersection of the rake faces A, i.e. the top surfaces of the worm, and the flanks B, i.e. the working sides of the worm. The number of cutting edges K equals to the thread number i of the worm, where i is a positive integer. The normal pitch P.sub.n of the working side of the worm is equal to the normal base pitch t.sub.b of the machined gear .pi.m.sub.n COS.alpha..sub.n where m.sub.n is the normal module of the machined gear; and .alpha..sub.n is the normal pressure angle at the reference circle of the machined gear. The lead angle .lambda. of the helix cutting edge is calculated by the formula Sin.lambda.=(im.sub.n COS.alpha..sub.n)/2R where R is the radius of cylindrical helix cutting edge K, and the helix lead P of the helix cutting edge P=(i.pi.m.sub.n COS.alpha..sub.n)/COS.lambda..

Abstract: A system is provided for inventorying a plurality of items in a supply. The items include a plurality of subgroupings of similar "item types" which are distributed in a selected pattern among a plurality of known locations. The inventory process is done by a plurality of known inventory entities. The system includes a plurality of type identifiers, each carrying machine readable data specific to an item type, for distinguishing a particular item type from other item types. A plurality of sequential item identifiers are also provided for carrying machine readable data. A unique item identifier is applied to each item in the supply without regard to item type, for distinguishing each item from other items within and without a particular item type subgrouping. A device is provided for reading and storing machine readable data from the type identifiers and item identifiers.

Abstract: A frequency comb multiple access (FCMA) communications system in which address and message data are transmitted on a common channel to different users. The data transmitted are in the form of signatures, each of which consists of combined specific frequencies selected from a range of discrete frequencies available in the bandwidth of the common channel. Each signature corresponds to an address and to a data message directed to the address. This system does not require handshaking nor channel assignment. A transmitter and a receiver for the system are also disclosed.

Abstract: There is provided illuminating apparatus including an illuminating channel 10 defined between an incident surface 11, an emergent surface 12, an upper surface 13 and a lower surface 14. The upper surface 13 includes end portions 15 which may be adhered to the lower end portions 16 of an adjacent illuminating channel. The portion of the upper surface 13 between the end portions 15 comprises a steeply inclined outer portion 17, a horizontal central portion 20 and a shallow inner inclined portion 21. Light entering the incident face 31 at a low angle of incidence is reflected by total internal reflection in turn from the lower outer surface 32 of a first cavity 33, the central portion of the upper surface 34 of a second cavity 35, and then the inner lower surface 36 of the first cavity 33 before emerging from the emergent face 37.

Abstract: Method and apparatus for the electromagnetic dynamic plasticating of polymer materials includes a magnetic moving body which is supported both axially and radially by a magnetic levitation gap. The magnetic body is rotated in non-steady state vibration within an electromagnetic winding and cooperates with a stationary body to form a processing space for the polymer material.

Abstract: This invention is related to the process and apparatus for applying stressed skin sheet coverings to large passenger vehicles. The apparatus for the process, provided by this invention includes a single phase transformer, conductors, electric contactors and a guiding apparatus. The present invention uses a specialized transformer, capable of producing a strong electric current of low voltage as an energy source, utilizing the steel skin sheet as a resistor element in the output circuit, welding the steel sheet onto the frame while the steel sheet is heated by the electric current passing through the sheet, thereby elongating the sheet at a set value due to the rise in temperature, cutting off the electricity and welding the upper and lower sides quickly onto the frame, thus finishing the process of skin covering and resulting in residual stresses within the steel skin sheet.

Abstract: This invention relates to a lithum-containing carbon anode employed in the process of producing aluminum metal where the lithium compounds in an amount of 0.1 to 1.5 percent by weight were added into the carbon mass made of pitch and calcined coke to produce a Soderberg anode and carbon mass of prebaked anode. Compared with the ordinary carbon anode used in the production of aluminum, the anode overvoltage will be reduced about 100 to about 200 mV. Therefore, the energy consumption will be decreased by about 300 to about 600 Kwh. In addition, the current efficiency will be increased by 1 to 2 percent.

Abstract: A method of treating substrate surfaces with the aid of a plasma such as etching, deposition etc. In the practice of the method, the plasma flows from its place of generation to the treatment-chamber, and in which method the plasma-generator is flushed through with a flushing gas. Preferably, and firstly after the flushing gas has passed the cathodes, the reactant is fed to the plasma-generator. The invention includes the reactor necessary for carrying out the method.

Abstract: Optical lenses, particularly spectacle, contact and intra-ocular lenses manufactured from glass or plastic. The lenses are provided with a hydrophilic coating which is immobilized upon the lens to provide permanent lubricity and uniform wetting characteristics.

Abstract: An adjustable support for an optical or other instrument (e.g. a binocular microscope for use by a surgeon in neurosurgery) which readily permits adjustment in the position of the instrument in a predetermined spatial envelope and/or adjustment of the orientation of the instrument at any given position within that envelope, and which is compact, relatively inexpensive to manufacture, easy to adjust, and incorporates a high degree of safety, comprises a rod-like carrier, supporting the instrument at one end and an adjustable counterweight at the other, mounted, by a ball joint arrangement on a linkage system rotatably supported on a column. The ball joint arrangement and the other joint arrangements in the linkage system are provided with clamping devices, normally urged to clamping position by springs but released by the application of air pressure under control of a switch device.