Abstract: A utility knife includes a housing with multiple interior spaces, each for holding a utility blade slidably therein. A U-shaped spring-clip has two ends rotationally fixed with the housing. A catch section of the spring clip traverses a retention slot formed in the housing. The spring clip may be pushed from an inward position into an outward position to allow the utility blade to pass from the interior space out through a slot to exit an end of the housing. When the spring clip is released with a retaining notch of the utility blade aligned with the retention slot, the retaining clip engages the retaining notch to capture the utility blade in a deployed position. Preferably the housing comprises several thin metal plates stacked together and fastened with a plurality of mechanical fasteners.

Abstract: A utility knife includes a housing with multiple interior spaces, each for holding a utility blade slidably therein. A U-shaped spring-clip has two ends rotationally fixed with the housing. A catch section of the spring clip traverses a retention slot formed in the housing. The spring clip may be pushed from an inward position into an outward position to allow the utility blade to pass from the interior space out through a slot to exit an end of the housing. When the spring clip is released with a retaining notch of the utility blade aligned with the retention slot, the retaining clip engages the retaining notch to capture the utility blade in a deployed position. Preferably the housing comprises several thin metal plates stacked together and fastened with a plurality of mechanical fasteners.

Abstract: A method and apparatus for directly estimating depleted ionosphere delay in a GPS receiver and using the estimate for improved navigation precision in satellite based augmentation systems.

Abstract: A method and apparatus for directly estimating depleted ionosphere delay in a GPS receiver and using the estimate for improved navigation precision in satellite based augmentation systems.

Abstract: Improving accuracy of frequency response measurements of linear systems using modulation transfer function test compensation. An optical imaging system illuminates and images an input test pattern. A processor measures a modulation transfer function. The processor determines a compensating factor for error in the input test pattern duty cycle. The driving function for the measurement is a test pattern having a periodic waveform approximating a square wave with an error in duty cycle. A windowed fast fourier transform on a greyscale image of the test pattern generates odd harmonics. Adjusting amplitude values of the odd harmonics corrects for the error in resolution target duty cycle.