Abstract: An authentication system of a terminal on a public switched telephone network provides a security node associated with a local exchange and a network terminal. For one-way authentication, the terminal responds to a call initiation by sending a unique authentication code comprising a number and a secret key encrypted according to a first algorithm, the secret key being specific to the terminal. The security node constructs the expected authentication code from the number, using the first algorithm and a second key which is a function of a terminal identification number, and compares the expected code with the received code. In two-way authentication, the security node responds to the call initiation by sending a transaction number to the terminal encrypted according to a second algorithm. The terminal generates the authentication code as a function of the first algorithm, the secret key and the transaction number. The authentication code is sent back to the security node.

Abstract: The present invention provides a vertical seismic imaging apparatus and method for evaluation a reservoir. The invention includes a plurality of sensors disposed in a well borehole either permanently cemented in place or retrievably disposed using a series of clamps to attach the sensors to the borehole wall. Each sensor uses one or more forced balanced controlled accelerometers to detect acoustic energy in the formation.

Abstract: The present invention, in general, provides for a testing system and method for detecting defects within a circuit. A current signature of the quiescent current of the circuit is determined, and certain constant values are calculated based on the current signature using a linear iterative regression. A defect free state for the circuit associated with a minimum quiescent current (IDDQ) is then determined. The IDDQ of the circuit for this state is measured, and a signal indicating the IDDQ at this state is used along with the aforementioned constant values to create upper and lower threshold values. Thereafter, signals indicating the value of IDDQ for a plurality of other states are compared to the upper and lower threshold values. The circuit is determined to be defective if the values of any of the signals is greater than the upper threshold value or is less than the lower threshold value.

Abstract: A method for operating a data processing system to provide an estimate of the leakage current expected from an integrated circuit having a known test vector applied thereto. The method generates a graph having a first node connected to a terminal maintained at a first power supply potential and a second node connected to a terminal maintained at a second power supply potential, the first and second power supply potentials having a potential difference of VDD. Each edge represents a source-drain connected transistor connected between two nodes as a switch having a resistance that depends on whether the transistor is “on” or “off” when the test signals are present. Each node in the graph is assigned a value of 0 or 1, together with the strength of that value. The assignment process also verifies that the circuit is in a valid static state.

Abstract: A confocal microscope including a light source; an optical fiber bundle defining a plurality of optical channels for receiving light from the light source and for transmitting the light to an object and for allowing light to return from the object through the optical fiber bundle; a switch for selectively switching selected fibers in the optical fiber bundle so as to allow light to selectively be transmitted and returned through individual optical channels until an image of the object is produced; and a detector for receiving returned light from the optical fiber bundle to enable the image of the object to be produced.

Abstract: A waterbed mattress is disclosed having a cushioned box shaped frame with a base sheet securely attached to the box shaped frame, the combination forming therein cavity. A plurality of elongated fluid filled containers are disposed within the cavity, and two flat rectangularly shaped fluid filled envelopes are disposed over the elongated containers. The base sheet serves to hold the box shaped frame in substantially a rectangular shape. Additionally, the flat fluid filled envelopes provide a mattress with improved wave motion damping characteristics.