System and method for verifying the integrity of contents within a computer file. A security value S is stored within the file. A verification function f is applied against the entire contents of the file including S, where f is a function of S. Results R of the applying step are compared against a preselected value r, where r is not stored within the file. When R equals r, a determination is made that the file has not been modified. f is typically a distributive invertible function such as the ...

A data integrity checking apparatus including an array of n latch circuits, each latch circuit having an input terminal and an output terminal, an array of n exclusive OR (XOR) gates, each XOR gate having two inputs and an output, the output terminals of the XOR gates are connected to the input terminals of respective ones of the latch circuits, the XOR gates receiving as one input bit-rotated words from the outputs of the latch circuits and as another input successive words of the data to be ch...

Impedance between potential sensing electrodes of a high impedance meter is measured by applying a ramp waveform through a capacitor coupled to one of the electrodes to generate a substantially constant current, a measure of impedance being obtained by comparing this to the potential developed across the electrodes when a different current is flowing.

An exemplary implementation of the invention is a process for forming passivation protection on a semiconductor assembly by the steps of: forming a layer of oxide over patterned metal lines having sidewalls; forming a first passivation layer of silicon nitride over the layer of oxide such that the first passivation layer of silicon nitride resides along the sidewalls of metal lines and pinches off a gap between the metal lines; performing a facet etch to remove material from the edges of the fir...

Thromboresistant biomedical articles are provided which are useful in the fields of subdermal surgical implants, laboratory apparatus and blood containers. These articles have at least a thin surface coating of an organic polymeric material having fluoroalkyl side chains and simple anionic side groups.

An interrogation unit is connected between the feed and return line of a McCulloh alarm circuit (i.e. between a McCulloh receiver and a plurality of McCulloh transmitter) to maintain the line current relatively constant and not disturb or interfere with the basic McCulloh alarm function. The interrogation unit transmits a command signal to receive units which are serially connected with selected McCulloh transmitters in the basic McCulloh circuit. The command signal is a pulse having a polarity ...

A circuit for use with a sensor located in a hazardous area such as in an atmosphere of explosive gases, organized to prevent electrical power at the sensor from exceeding prescribed levels even upon reasonably foreseeable failures of parts of the circuit. The circuit, which is located in a non-hazardous area, includes an indicator, such as a relay-controlled alarm, to respond to the sensor, and terminals for connection to a source of line voltage. Two voltage step-down transformers have their s...

A building structure composed of column-like discontinuous compression members held by a plurality of tension elements, the column-like compression members being held in spaced relation by tension elements attached adjacent the ends of the column-like compression members. In the form shown, there are what can be termed two substructures, one at the top and one at the bottom, each substructure having pentagonal configurations of parallel lesser circles formed by column-like members and tension el...

A seal integrity verification system scans for changes in impedance in a seal with integral coaxial waveguide, twisted pair wires, parallel ribbon wires or parallel wires. The wires are monitored by a TDR to note changes in impedance. The changes indicate the location where the seal is not under proper compression to ensure a tight fit. This is especially useful in verifying that watertight doors on ships or submarines are sealing properly when shut.

Techniques are provided to manage the integrity of data stored in two or more data management systems by detecting inconsistencies between the data management systems. The techniques identify missing records in one or more data management systems by comparing the records in the data management systems. For records that exist in two or more data management systems, the techniques identify records that are not identical in the data management systems. A user checkpoint is provided between the iden...