Abstract: A process for implementing shading corrections in a video projector. The process selects a color to be shaded, and then sets a projector video level at a selected high video level. A target brightness map is then generated for each of a plurality of preselected shading correction application points at the selected high video level. The process sets the projector video level at a selected low video level, and generates a target brightness map for each of the plurality of shading correction application points at the low video level. Actual light levels are then measured at both the high and low video levels for each shading correction application point, and differences between the target and measured brightness values are minimized. The shading process of the present invention is automatically preformed during projector set-up, and thereby eliminates the inherent subjective and time consuming need for conventional manual shading processes.

Abstract: The photo-sensitive detector region of conventional Impurity Band Conduction (IBC) detector (also known as a Blocked Impurity Band [BIB] detector) is divided into a wide detection (or collection) region and a narrow gain region by means of tailoring the doping profile. The narrow gain region is that portion of the photo-sensitive detector region closest to the blocking layer, where the electric field is the largest, whose As concentration is made smaller (in the range of 2 to 5.times.10.sup.17 cm.sup.-3) to increase the impact ionization coefficient by decreasing the electron scattering. The wide detection region is that portion of the photo-sensitive detector region furthest from the blocking layer, where the electric field is smallest and the As concentration is larger (in the range of 5 to 8.times.10.sup.17 cm.sup.-3) to decrease the impact ionization coefficient by increasing the electron scattering.

Abstract: An up-down counter is fed pulses generated manually and/or automatically from either or any of two or more command sources. Gating circuitry ahead of the up-down counter may be used to enable counts from only one source at a time. The output of the counter represents the magnitude of the parameter to be controlled. The purpose is to transfer control of a parameter to any of several command sources without changing the value of the parameter, thereby achieving "stepless" switching. Only one counter is needed regardless of the number of command sources, no synchronizing circuitry is required, and switching is provided with no steps or delays. Multiple command sources may be active simultaneously when command source input gating is not used ahead of the up-down parameter magnitude counter.

Abstract: Minerals, especially coals for power generation, can be subjected to froth flotation using as a collector a liquid which contains at least 21% aromatics or at least 41% naphthenes. Improvements in froth yield and ash-in-tailings compared with commercial products are demonstrated.

Abstract: An insulating board of excellent properties is made from a core of foamed phenol-formaldehyde resin which has a closed cell content of at least 85%, laminated on at least one face using a water-based natural rubber latex adhesive with a glass fibre tissue or cloth. The laminate has good fire resistance and can be bonded to roofs etc. using hot bitumen.