Abstract: A matrix system for a battery, which includes a first parameter of power usage and a first requirement, which designates a portion of the first parameter is disclosed. The system further includes a second parameter of temperature and a second requirement, which designates a portion of the second parameter. Also, a third parameter of state of charge and a third requirement, which designates a portion of the third parameter, is described. The portions of the first, second and third parameters intersect to form a volume.

Abstract: A method for designing an IC package having a plastic encapsulated portion and a lead frame portion that are bonded together at a bonding interface includes selecting material candidates for each of the plastic encapsulated portion and the lead frame portion to obtain possible material combinations. A peeling stress and a shear stress at the bonding interface for each possible material combination is determined. A design material combination from all of the possible material combinations is then selected based on a singularity parameter and stress intensity factors of the peeling stress and the shear stress. To enhance the IC package, a circular fillet feature having a radius is added to a singularity point at the bonding interface of the IC package to reduce the stress at the singularity point.

Abstract: A vehicle fuel system has on-board diagnostics for leak testing with correction for different operating conditions. An electronic control unit (ECU) is arranged to carry out a periodic two stage leak test, when the engine is running. Stage A includes evacuation of the fuel tank, monitoring bleedup and recording the pressure rise dP.sub.-- A over a predetermined period A following increase of pressure to a predetermined value p2. Stage B includes measuring the amount dP.sub.-- B by which the pressure in the tank rises above atmospheric due to vapor generation over a predetermined period B following venting and closure fuel system. The ECU calculates a value X representative of leakage from the difference between dP.sub.-- A and dP.sub.-- B using a scaling factor K. The test duration is adjusted in accordance with measured values of fuel level and ambient temperature to ensure that the measured pressure changes are dependent on leakage over a range of operating conditions.

Abstract: A method of operating an oxygen sensor in the exhaust stream of an engine. The oxygen sensor includes a zirconia plate (14) mounted to two electrodes (16,18), covered with porous layers (20,22). The two porous layers (20,22) are designed to sense the two conditions of air/fuel mixture, lean and rich, by creating a delay in the sensing of the rate of transmission of oxygen through one of these layers (20,22). The method includes flowing exhaust gas over the sensor, maintaining essentially no flow of current through the leads when the exhaust gas maintains a state of rich or lean air/fuel ratio, and sensing induced emf spikes between the leads as the exhaust gas stream transitions between rich and lean air/fuel ratios.