Abstract: There is described a keyboard including user-operable alpha-numeric keys. One or more identification devices associated with the user-operable keys are included in the keyboard. When placed in proximity to the keyboard, the one or more identification devices selectively communicate with a digital apparatus in response to user-actuation of the user-operable keys. The keyboard comprises a flexible substrate for enabling the keyboard to be folded into a non-deployed inactive state, and unfolded into a deployed active state for communicating with the digital apparatus. When in proximity thereto, the keyboard communicates with the apparatus by way of near-field magnetic and/or electrostatic coupling.

Abstract: There is described a keyboard including user-operable alpha-numeric keys. One or more identification devices associated with the user-operable keys are included in the keyboard. When placed in proximity to the keyboard, the one or more identification devices selectively communicate with a digital apparatus in response to user-actuation of the user-operable keys. The keyboard comprises a flexible substrate for enabling the keyboard to be folded into a non-deployed inactive state, and unfolded into a deployed active state for communicating with the digital apparatus. When in proximity thereto, the keyboard communicates with the apparatus by way of near-field magnetic and/or electrostatic coupling.

Abstract: A method for preventing deposits or build-ups of dust in off-gas channels for dust-containing off-gases from electrothermal smelting furnaces. This is done by blowing an additional gas tangentially into the furnace off-gas channels at the positions where build-ups or deposits of dust normally occurs. Hence a gas spiral is provided between the inner wall of the furnace off-gas channels and the dust-containing, hot furnace off-gas. Recirculated and cooled furnace off-gas is preferably used as additional gas. For open furnaces where the furnace off-gas is completely combusted before it enters into the furnace off-gas channels, air can be used as additional gas. The temperature of the additional gas is preferably kept below the sintering temperature of the dust in the furnace off-gas.