elsevier science technology apr 1994 (3 risultati)

Buch. Condizione: Neu. Neuware - This volume contains selected papers from the 10th Interdisciplinary Workshop in Informatics and Psychology which had as its theme Cognitive Aspects in Visual Languages and Interfaces. Visual languages in general, visual programming languages in particular, and graphical or visual user interfaces are increasingly regarded as important improvements for the interaction between people and artifacts. Visual and graphical user interfaces have already a history of a number of years in terms of research and development. The focus on visual languages and visual programming languages, however, is more recent. The development of graphical user interfaces was accompanied and reinforced by psychological research but visual languages are still mainly inventions of designers and not designed on the basis of principles derived also from knowledge of psychology or other behavioral sciences.

Buch. Condizione: Neu. Neuware - This book introduces the reader in a systematical way to the design philosophy behind vector control systems. The mathematical motor models based on complex-space vector descriptions as well as the control structures for DC motors provide a perfect basis for explaining the principles of AC motor vector control. An in-depth review of electromagnetic transients in induction motors under various methods of frequency control is given. This is explained with the help of appropriate block schemes and new equivalent circuits. Properties of AC motors under non-sinusoidal supply are reviewed. The basic power converter topologies applied in motor control technology as well as symmetry and loss reduction problems are discussed. Some examples of controller design methods are presented step by step. An important feature of the book is that it contains many examples of systems applied in practical engineering as well as simulation and experimental results. The volume will be of interest to all those familiar with the basics of electrical machines and control systems theory. Therefore, it is recommended to students of electrical, electronics and mechanics departments. The book can also be used by those working in industry, who are interested in modern power electronics, drives and motion control, robotics as well as automation of industrial processes.

Buch. Condizione: Neu. Neuware - The apatites and related calcium phosphates have been of considerable interest to biologists, mineralogists, and inorganic and industrial chemists for many years. This book contains a detailed description of the structures and structural interrelationships of the calcium orthophosphates, including the apatites. Their preparation, crystal growth and dissolution, chemical reactions including thermal decomposition, IR, Raman and NMR spectra and various physical properties are discussed. Apatites other than those containing calcium and phosphorus are included. Synthetic, mineral and biological carbonate apatites are also considered. A wide, but critical coverage of the literature is given, which includes a substantial amount not written in English. Research from many disciplines is included which results in a comprehensive compilation of recent work.