Re-invented in the early 1990s on both sides of the Atlantic, Monolithic Active Pixel Sensors (MAPS) in a CMOS technology have slowly invaded the world of consumer imaging and are now on the edge of becoming the first technology in this field, previously dominated by Charge-Coupled Devices (CCD). Thanks to the advantages brought by the use of standard CMOS technology, MAPS have great potential in many areas including function integration, leading to the concept of a camera-on-a-chip, pixel size, random access to selected region-of-interest, low power, higher speed and radiation resistance. In many ways, MAPS have introduced a new way of doing imaging. Despite their success in the consumer arena, MAPS are still to make a definitive impact in the world of scientific imaging. This paper first briefly reviews the way radiation is detected by a CMOS sensor, before analysing the main noise source and its relationship with the full well capacity and the dynamic range. This paper will also show first examples of scientific results, obtained in the detection of low-energy electrons.
The planning, execution and preliminary results of a major Anglo-German explosion seismic project are presented in this, paper I of a series. This Lithospheric Seismic Profile in Britain (LISPB) was planned as a reversed 1000 km line between two major sea-shot points off Cape Wrath in Scotland and one in the English Channel; additional sea-shots and intermediate land-shots were fired to give reversed and overlapping crustal coverage (to 180–400 km distance) along the line. In all, 29 shots were fired and 60 mobile magnetic tape stations recorded three-components of ground motion. The resulting 14 crustal and three long-range profiles have observations at intervals of typically 2–4 km. Recordings have been digitized and four examples of filtered, computer-plotted record sections are presented to illustrate data quality. In a preliminary analysis, phase correlations are discussed and some models presented; the latter especially are more relevant to future interpretations than to geological or tectonic problems. However, significant variations in crustal thickness and in the nature of the crust-mantle transition do seem to occur beneath the British Isles.
In general, pollen and spores are present in the sediments of the deep ocean basins, particularly in deposits of terrigenous origin. Pollen spectra of abyssal sediments reflect the vegetation of adjacent land masses. Deposits of abyssal plains and oceanic rises with relatively little local relief, situated in the temporate zones, present the most favorable opportunities for obtaining a continuous history of vegetational and climatic changes during the Quaternary.The very slow rate of deposition in the ocean basins and the need to have relatively large core samples in order to obtain a sufficient number of pollen grains impose a limit on the detail with which reconstruction of vegetation and climate can be accomplished. Occurrence of reworked plant microfossils presents difficulties particularly where pre-Quaternary sediments are exposed on the continental shelf or slope.