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Saqqaq and Dorset sites excavated by the author in the southern part of Qeqertarsuup Tunua (Disko Bugt) form the empirical basis for a comparison of Saqqaq and Dorset settlement in the area. Earlier reconstructions of the cultural history were based mainly on observations of stratified middens. In contrast to this, the present work focuses on the horizontal dimension within the archaeological record. As a consequence, settlement patterns, dwelling types and the spatial organisation of dwellings are the principal objectives. Saqqaq and Dorset settlement patterns are broadly similar and it is concluded that there is little evidence to suggest any major difference in economy or adaptation between the two periods. Both Saqqaq and Dorset settlement patterns are characterised by a number of large settlements located strategically near the most productive biotopes. Minor settlements, most often occupied during the warm season, are found within the catchment area, indicating annual recurring dispersal of the population during the warmer months. Only Sydostbugten, in Southeastern Qeqertarsuup Tunua, appears to exhibit significant differences between Saqqaq and Dorset settlement patterns. Large Dorset settlements have not been found in Sydostbugten and it is suggested that this area, probably due to climatic oscillations, was less attractive for settlement during the Dorset period than it was in the Saqqaq. Consequently, the Dorset people seem only to have utilised Sydostbugten for specialised seasonal camps. Saqqaq and Dorset accommodation comprises distinct summer and winter dwellings. During both periods, the summer dwellings are characterised by what are believed to be single family tents. These occur in two principal varieties: Tent rings, with a central hearth, and mid-passage tent rings, where the interior is divided in two by parallel lines of stones. This difference in architecture is suggested to result from variation in the social composition of the inhabitants. Winter dwellings of both the Saqqaq and Dorset cultures are characterised by more solidly built structures. In the Saqqaq culture there are platform dwellings and mid-passage structures filled with fire-cracked rocks. During the Dorset, the winter dwellings are characterised by double-platform dwellings, in which a central floor area divides the interior into two platforms that are often paved. The presence of more than one hearth or lamp stand, as well as mirrored distributions of the most frequent tool categories to the left and right of the central floor area, is interpreted as a result of these dwellings being occupied by two families. Chapter 7 focuses on Saqqaq raw material distribution from killiaq sources in the vicinity of Qaarsut and Angissat. The raw material distribution from these two sources is characterised as a regional and local system. The procurement and subsequent distribution of raw materials from Angissat in Southern Qeqertarsuup Tunua appears thus to have been imbedded in the local resource exploitation. Much of the raw material extraction appears to have been carried out by hunting parties visiting the outcrop during summer hunting trips. In contrast to this, Qaarsut at Nuussuaq shows evidence of a more comprehensive production of preforms, which were distributed throughout Western Greenland. Economically as well as socially, there appear to be numerous similarities between the Saqqaq and Dorset cultures. However, when evaluating the radiocarbon dates, there appears to be discontinuity between the two periods as is also suggested by earlier excavations of stratified deposits. In Sisimiut District, to the south of Qeqertarsuup Tunua, the latest Saqqaq dates overlap with the oldest Dorset dates. Theoretically, there could be continuity between the two periods outside Qeqertarsuup Tunua, however the archaeological evidence for such a development has yet to be found. When the cultural history of Qeqertarsuup Tunua is compared with that of Peary Land, the dwelling types and chronological units appear very similar. In the case of Dorset and Independence II, the similarities also extend to include the lithic inventory. As a consequence it is difficult to maintain a division between Dorset in Western and Southern Greenland and Independence II in the High Arctic.

Excavations (Archaeology) --- Saqqaq culture. --- Dorset culture --- Eskimos --- Archaeological digs --- Archaeological excavations --- Digs (Archaeology) --- Excavation sites (Archaeology) --- Ruins --- Sites, Excavation (Archaeology) --- Archaeology --- Antiquities

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Interactive television --- Congresses. --- Social aspects --- Interactive television -- Congresses. --- Interactive television -- Social aspects -- Congresses. --- Electrical & Computer Engineering --- Engineering & Applied Sciences --- Journalism & Communications --- Electrical Engineering --- Radio & TV Broadcasting --- Computer Science --- Information Technology --- Computer Science (Hardware & Networks) --- Computer science. --- Multimedia information systems. --- User interfaces (Computer systems). --- Computer graphics. --- Application software. --- Computer Science. --- User Interfaces and Human Computer Interaction. --- Information Systems Applications (incl. Internet). --- Multimedia Information Systems. --- Computer Graphics. --- Computer Appl. in Arts and Humanities. --- Application computer programs --- Application computer software --- Applications software --- Apps (Computer software) --- Computer software --- Automatic drafting --- Graphic data processing --- Graphics, Computer --- Computer art --- Graphic arts --- Electronic data processing --- Engineering graphics --- Image processing --- Interfaces, User (Computer systems) --- Human-machine systems --- Human-computer interaction --- Computer-based multimedia information systems --- Multimedia computing --- Multimedia information systems --- Multimedia knowledge systems --- Information storage and retrieval systems --- Informatics --- Science --- Digital techniques --- Television --- Multimedia systems. --- Information systems. --- Amsterdam <2007>

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This book is a comprehensive review of high-temperature polymer electrolyte membrane fuel cells (PEMFCs).  PEMFCs are the preferred fuel cells for a variety of applications such as automobiles, cogeneration of heat and power units, emergency power, and portable electronics. The first 5 chapters of the book describe rationalization and illustration of approaches to high temperature PEM systems. Chapters 6 - 13 are devoted to fabrication, optimization and characterization of phosphoric acid-doped polybenzimidazole membranes, the very first electrolyte system that has demonstrated the concept of and motivated extensive research activity in the field. The last 11 chapters summarize the state-of-the-art of technological development of high temperature-PEMFCs based on acid doped PBI membranes including catalysts, electrodes, MEAs, bipolar plates, modelling, stacking, diagnostics and applications.

Electrical Engineering --- Electrical & Computer Engineering --- Engineering & Applied Sciences --- Proton exchange membrane fuel cells. --- Fuel cells. --- PEFCs (Fuel cells) --- PEM fuel cells --- PEMFCs (Fuel cells) --- Polymer electrolyte fuel cells --- Polymer electrolyte membrane fuel cells --- Proton conducting membrane fuel cells --- Direct energy conversion --- Electric batteries --- Electric power production from chemical action --- Electrochemistry --- Fuel cells --- Chemistry. --- Chemical engineering. --- Polymers. --- Optical materials. --- Energy Systems. --- Electrochemistry. --- Industrial Chemistry/Chemical Engineering. --- Polymer Sciences. --- Optical and Electronic Materials. --- Optics --- Materials --- Polymere --- Polymeride --- Polymers and polymerization --- Macromolecules --- Chemistry, Industrial --- Engineering, Chemical --- Industrial chemistry --- Engineering --- Chemistry, Technical --- Metallurgy --- Physical sciences --- Energy systems. --- Polymers  . --- Electronic materials. --- Chemistry, Physical and theoretical --- Electronic materials