Abstract: Box cursors consisting of lines of identical thickness are displayed using a bit inverting technique so that overlapped portions of the cursors may be differentiated. Masks are prepared, one for each of the box cursors, which have patterns which, when exclusive ORed, result in a pattern including 1 bits. The box cursors are generated having lines corresponding to respective ones of the masks. Thus, even though box cursors may overlap on the display, the side or sides of the overlapping cursors will be displayed as a pattern of pel points corresponding to the pattern including 1 bits.

Abstract: An improved mixed object editor flows text around and into irregularly shaped graphic objects on a page so that all the "white" space on the page is filled. An irregularly shaped window which generally conforms to the shape of the graphic object is first created. Then the boundaries of text lines which intersect the irregularly shaped window are determined. Text is next placed in the available text space.

Abstract: An asynchronous communication system includes a clock recovery circuit (2) to which the received signal (1) is applied and which provides recovered data (3) to a frame delimiter detector (4). The frame delimiter detector in turn generates a frame start signal to a frame sync generator (16) and provides asynchronous data (5) to an elastic buffer (7) which provides as its output the synchronized data (8). The clock recovery circuit also provides a recovered clock signal (9) to a clock guarding circuit (12). The clock guarding circuit (12) receives a local clock signal (11) and produces a guarded clock signal (13) and a data clock signal (14), both of which are supplied to the frame sync generator and the elastic buffer. The frame sync generator produces a frame sync signal having a duration determined by the active edges of the guarded clock and data clock signals, and this signal is used to load a mask pattern in the elastic buffer.

Abstract: A recirculating sand filter system for the treatment of waste water comprises a septic tank (10) for receiving waste water, a recirculating pump tank (18) connected to the septic tank for receiving effluent from the septic tank and one or more sand filter modules (12, 14). The recirculating pump tank has a pump (48) connected to a pump outlet line (32) connected to the sand filter modules. A distribution pipe (28) connected to the pump outlet line is positioned to spray water over a surface of the sand filters. The pump is controlled by a timer (74) to periodically pump water to dose the sand filters. The sand filters have one or more collection pipes (34, 36) at the bottom of the filter for collecting filtrate and returning the filtrate to the recirculating pump tank via a return line (42) by gravity feed. A recirculating valve (52) in the recirculating pump tank is connected between the return line and a discharge line exiting the recirculating pump tank.

Abstract: The menu hierarchy of one or more computer programs on one or more computer systems is visually displayed in a graphical tree structure to facilitate the navigation by a user from one menu in a hierarchical structure of menus to another. Navigation from one menu to another is accomplished by selecting a menu in the graphical menu tree using a pointing device. The navigation may be from one menu to another in the hierarchy of one application program in a computer system or from one menu in the program to a specific menu in the hierarchy of another application program in the computer system or in another computer system. The benefits of the technique are expanded function for intra and interwindow navigation, enhanced learning of the computer system by visual presentation of capabilities and structure, and reduced learning requirements for the user to achieve navigation.

Abstract: A recirculating sand filter system for the treatment of waste water comprises a septic tank (10) for receiving waste water, a recirculating pump tank (18) connected to the septic tank for receiving effluent from the septic tank, and one or more sand filter modules (12, 14). The recirculating pump tank has a pump (48) connected to a pump outlet line (32) connected to the sand filter modules. A distribution pipe (28) connected to the pump outlet line is positioned to spray water over a surface of the sand filters. The pump is controlled by a timer (74) to periodically pump water to dose the sand filters. The sand filters have one or more collection pipes (34, 36) at the bottom of the filter for collecting filtrate and returning the filtrate to the recirculating pump tank via a return line (42) by gravity feed. A recirculating valve (52) in the recirculating pump tank is connected between the return line and a discharge line exiting the recirculating pump tank.

Abstract: A computer automated method and system is used to time transformers to produce a resonant circuit for matching elements to a circuit is disclosed. The modeling method uses a computer to select discrete values for resistive and capacitive loads to be connected to the secondary of a transformer. For each combination of resistive and capacitive load connected to the secondary, the circuit is measured for phase angle. This data is used by the computer software to predict the tuning of the transformer to a load combination that is not actually connected to the transformer. This is done by determining two load lines for actual values of resistance and capacitance connected to the transformer secondary and then interpolating between the two load lines using a logarithmic equation. An option provided to the operator is to specify the value of the load capacitance or not. If the load capacitance is specified, the computer computes the phase angle for that value of load capacitance.

Abstract: A method for the intelligent, in-line, dynamic editing of documents containing mixed object types on a computer work station is disclosed. The mixed object types may be text objects, draw graphics objects, business graphics objects, and tables objects. The editor executes actions on use selected objects and attributes based on internal knowledge of the object type selected rather than by explicit user commands. This procedure provides a simple user interface that makes manipulation of objects and attributes and command execution transparent to the user.

Abstract: A following voltage/current regulator includes a field effect transistor (FET) (48) connected in series between an unregulated voltage source (44) and a load, such as a motor bridge circuit (50). The conduction of the FET is controlled by a control circuit (56) which measures the input voltage to the FET source, the output voltage from the FET drain and the current drawn by the load. Initially, when power is turned on, the inrush current to the load is limited until a predetermined voltage differential between the input and output voltages is achieved at steady state. Then, the voltage regulator maintains the predetermined voltage differential to provide a well regulated output voltage to the load despite fluctuations in supply voltage. This "following" action limits the heat disipation and protects the FET. Because the voltage regulator uses no inductors or transformers, there are no saturation problems and the circuit may be compactly packaged.

Abstract: An automatic overvoltage protection circuit is provided for an electrical power supply of the type comprising a variable speed three phase alternator (50) having a permanent magnet rotor and three stator output windings (51, 52 and 53), a gated three phase rectifier bridge (60) connected to the three stator output windings and producing a d.c. output voltage, and a control circuit (120) for supplying gating signals at controlled firing angles to the gated three phase rectifier bridge. The control circuit includes first, second and third reference circuits (73, 74 and 75) each including a resonant LRC circuit and connected to a respective one of the three stator output windings, a gating logic circuit (135) connected to the first, second and third reference circuits and providing six outputs, feedback means (122) connected to receive the d.c.

Abstract: A method for controlling processor access to input/output control units and devices connected to the control units to prevent control unit and device lookout due to the condition where the channel turn-around time becomes less than the device controller's housekeeping time is disclosed. The problem of control unit and device lockout is overcome by monitoring path and device activity for a given processor while at the same time keeping track of other processors waiting for a given path and device. When it is determined that a given number of consecutive input/output operations have been accomplished for a given processor and at the same time another processor requires this resource, then a busy condition will be asserted for new input/output requests from the current processor for the currently accessed path and/or device. This action forces the offending processor to wait until the controller and/or the device is again available.

Abstract: A conventional microwave over has been modified such that it may be used for plasma etching and cleaning. Oxygen or Argon gas is introduced into a vacuum chamber (18) inside a conventional microwave oven (10) that has been modified to allow gas from a canister outside the microwave oven to pass through the rear wall of the microwave oven into the vacuum chamber (18). A rotating antenna (16) ignites the gas to produce a uniform plasma which etches the substrate (28). Reaction by products are evacuated from the vacuum chamber by a vacuum pump positioned outside the microwave oven (10). The intensity of the microwaves can be adjusted for plasma etching via a maximum power control device which has been added to the electronic control circuit of the microwave oven. In addition, a vacuum chamber with a water cooling feature is provided to prevent thermal damage to the substrate during plasma processing.

Abstract: A microwave and millimeter wave hybrid or monolithic microstrip test probe assembly provides a noninvasive radio frequency test point in a microstrip circuit. The probe assembly comprises a microstrip coupler. (12) adjacent a microstrip line (10) in the circuit for sampling a small amount of microwave energy propagating along said microstrip line. A stripline circuit (20, 22 and 24) is connected to the microstrip coupler. The stripline circuit includes a pad area (24) and a probe (26) moveable to overlay the pad area. The probe forms a ground plane with respect to the pad area, and a coaxial line (34) has an outer conductor connected to the probe and an inner conductor projecting through a hole in the probe. The probe assembly provides an RF test point within a microstrip circuit which allows an accurate, calibrated and repeatable means of sampling a microstrip signal while not affecting the normal performance of the hybrid or monolithic circuit.

Abstract: A gravity operated switching circuit, having particular application in end of train equipment, allows the microprocessor circuit board in the equipment to be turned off. The circuit turns the power off when the equipment is laid on its side after a predetermined time constant, and when the equipment is again mounted in an upright position, the power is turned on after a different predetermined time constant. A modification of the basic circuit requires a reset button to be manually pressed to restore power after the equipment is again mounted in an upright position.

Abstract: A method for generating display screens for a set of application programs allows application programmers to write programs without having to code the specific locations on a computer display screen where information and data are to be displayed in fields of various display screens of the set of application programs. A series of screen management subroutines are callable from an application program. A display screen is defined by loading one or more arrays of screen specification data indicative of information and data to be displayed. The display screen may be defined by loading the arrays by an application program using data contained in a screen driver file or alternatively by supplying the data to the arrays by means of data statements. The display screen is managed by calling subroutines to read screen specifications, to display screen headings, to display data fields and to read data fields.

Abstract: An anti-stall motor drive circuit for a very slow running permanent magnet d.c. motor is disclosed. The slow running speed of the motor sometimes allows an insulating film to build up between the brushes and the commutator which causes the stalled condition. The motor (10) is connected in the collector circuit of a drive transistor (Q1) which has a current limiting resistor (R9) connected in its emitter circuit. A stalled condition of the motor (10) is sensed by a lack of output from a tachometer (16) output. The output of the tachometer is full wave rectified by an operational amplifier (22) and diodes (CR1 and CR2). The rectified tachometer voltage is applied to an integrator (24 and C1) having a clamping diode (CR7) connected in its feedback circuit. A zero output from the rectifier allows the integrator output to ramp up to a limiting value determined by the clamping diode.

Abstract: The procedure which allows users of a computer system comprising a plurality of computers connected in a local area network to share both file resources and application programs on the local area network without modification to existing programs which were designed to run in a non-network environment is disclosed. The local area network comprises a server computer and at least one remote computer. Starting the network comprises an initial program load of the operating system for each of the computers, loading the local area network control program, and then loading a hypervisor or "node enabler" program. At each of the remote computers, a request to load a program or access a data file is converted by the "node enabler" to a file sharing and record locking protocol message with is transmitted to the server computer. The server computer stores a program matrix with entries indicating which programs can be run on the network without conflicts with other systems including the server computer.

Abstract: A differential transformer is used as a feedback sensor for generating an error signal sensed at the face of an element of a sonar transducing array. This error signal is used to correct the excitation signal to the transducer to correct both phase and amplitude errors in the vibration of the radiating surface of the transducer. In this way, the transmitting beam pattern for the sonar array is improved. The differential transformer is capable of sensing the mechanical motion of the transducer radiating surface without being affected by a strong electric or magnetic field. By using a separate differential transformer sensor and processing circuit for each transducer in the array, electrical cross-talk between the individual elements of the array is eliminated.

Abstract: Certain applications require a CRT display to be well shielded against emitting RF electromagnetic energy. A shield placed at the neck portion of a CRT envelope inhibits RF emissions from being transmitted through the face portion of the CRT. The shield comprises longitudinal conductors for suppressing transverse magnetic (TM.sub.01, TM.sub.02 . . . ) mode emissions and circular conductors for suppressing transverse electric (TE.sub.01, TE.sub.02 . . . ) mode emissions. Placing the shield at the rear of the CRT envelope eliminates the need for covering the face portion of the CRT with an optically transparent screen. To eliminate RF emissions from the CRT display the housing is provided with a contiguous RF emission shield that is connected to the shield on the neck of the CRT. Alternatively, an internal RF emission shield would enclose the video circuitry which includes all potential sources of undesired RF emission.

Abstract: An academic quiz controller system includes first and second pluralities of identical and interchangeable response stations (11, 12, 13, 14 and 21, 22, 23, 24) each provided with a switch (17) and an indicator light (16) activated by the switch when pressed by a contestant. The first and second pluralities of response stations are serially connected by means of three pair telephone wire (10 and 20) and modular telephone jacks to form first and second strings of response stations. A microprocessor-controlled master console (30) has a plurality of indicators (33 and 34), one for each response station, a start switch (36) and a mode switch (37). The first and second strings of response stations are connected to the master console by means of three pair telephone wire (15 and 25) and modular telephone jacks as is a judge's switch pad (40) which is used for inputting an indication as to whether an answer is right or wrong.