Abstract: An exterior wall is kept free of moisture condensation in both heating and cooling seasons by four one-way valves that utilize pressure differentials of a chimney effect to ventilate the insulating cavity with air from the drier colder side, while maintaining a vapor barrier on the more humid warmer side.

Abstract: An exterior wall is kept free of moisture condensation in both heating and cooling seasons by four one-way valves that utilize pressure differentials of a chimney effect to ventilate the insulating cavity with air from the drier colder side, while maintaining a vapor barrier on the more humid warmer side.

Abstract: In a first embodiment, a gas-impermeable vapor barrier inner layer of a cold weather suit prevents condensation of body moisture in outer layers, thus preventing degradation of outer-layer insulating value. Body moisture vapor is collected by a network of tubes inside the inner layer, and fed through a one-way valve into a facemask, where it is added to inhaled air. Heat of vaporization of body moisture, and body heat lost to air convection, is thus recovered by displacing a like amount of heat of vaporization of moisture, and heat added to exhaled air, respectively, that would have been added by the lungs. The basic system can be further improved by additional gas-impermeable insulating layers, and by providing a coupling to detach the facemask from the tube network, so that the remaining tube network is inconspicuous within the suit. In a second embodiment, a heat exchanger also recovers heat, and heat of condensation, from exhaled air and uses it to pre-warm air entering the suit to be inhaled.

Abstract: A method for calibrating a circuit analyzer includes determining a plurality of initial technology parameters characterizing the circuit according to a timing model of the circuit. A delay along an entire logic path of the circuit is expressed as a function of the technology parameters. A benchmark set of circuit paths is determined which has fixed topology, device sizes, and wire capacitances. The technology parameters are then optimized to minimize error over the set of circuit paths to obtain optimized parameters for use in the timing model. The optimized technology parameters minimize the average error for the benchmark set of paths relative to SPICE or physical measurements. Average error is significantly reduced on a representative set of paths when compared to the conventional approach of separately measuring each parameter.

Abstract: In accordance with the invention, a conductive lead line extending between a source and a capacitance load has a width w(x) which is a function of the distance x. For many practical applications such as leads for multichip modules, w(x) can be taken as the exponential function of the distance from the load given by the equation below. For many applications w(x) can be adequately approximated by the first three terms of a power series representation: ##EQU1## where W.sub.0 is the width of the lead line at x=0, C.sub.0 is the load capacitance and C.sub.0 is the area capacitance. For VLSI applications w(x) is a friction which can be designated.noteq.E(W.sub.0, C.sub.0, C.sub.p, C.sub.S, x) where C.sub.p is the perimeter capacitance. E(W.sub.0, C.sub.0, C.sub.p, C.sub.S, x) is derived herein.