Abstract: An access control method is performed on an equipment item linked to elements for rendering at least one haptic signal on a haptic rendering surface, wherein the haptic signal is a touch-discernible texture. The method includes, after an access request has been obtained: ordering rendering of a haptic signal; obtaining information on detection of a gesture of response to the signal; of validating the gesture of response when the gesture detected corresponds to a gesture previously associated with the haptic signal rendered; and authorizing access following the validation of the gesture.

Abstract: An access control method is performed on an equipment item linked to elements for rendering at least one haptic signal on a haptic rendering surface, wherein the haptic signal is a touch-discernible texture. The method includes, after an access request has been obtained: ordering rendering of a haptic signal; obtaining information on detection of a gesture of response to the signal; of validating the gesture of response when the gesture detected corresponds to a gesture previously associated with the haptic signal rendered; and authorizing access following the validation of the gesture.

Abstract: A method and apparatus for monitoring the performance of an echo canceler within a telephone communications network is disclosed. In accordance with the method and apparatus of the present invention, an embedded echo-cancellation performance monitoring circuit comprises three separate units, namely, a test data injection unit, an echo path simulator unit, and a test data extraction unit. The test data injection unit is utilized to inject test data into a serial data stream intended for an echo canceler. The echo path simulator unit is utilized to simulate an echo path by attenuating the test data in the serial data stream and to loop the test data in the serial data stream back to the echo canceler. The test data extraction unit is utilized to extract the test data from a send-out data stream exiting from the echo canceler.

Abstract: Metallic copper is recovered from an ammoniacal copper sulfate solution by treating such solution with sulfur dioxide to form a precipitate of copper ammonium sulfite. The crystals are suspended in an acidic solution containing initially from 20 to 75 grams per liter of sulfuric acid, which preferably contains a substantial concentration (up to saturation) of ammonium sulfate, said solution containing from 40% to 70% by weight of such crystals, and the resulting suspension is heated at 140.degree.C. to 170.degree.C. and at 150 to 220 psi. until substantially all the copper ammonium sulfite has been converted to metallic copper. The metallic copper thereafter is separated from the residual solution.