Dr W J Jenkins In 1977 when the Sheffield Transfusion Centre took delivery of the first GROUPAMATIC blood grouping machine in the UK it was equipped with a sample identification system involving complicated and expensive disposable punched cards. In fact, the cards were so expensive that Dr Wagstaff was unable to find the revenue to support the system. A year later, when Brentwood took delivery of a GROUPAMATIC, we were faced with the same problem, but by chance we heard that KONTRON was developing a laser scanning system for bar code labels and we were able to have our machine modified. Subsequently the Sheffield machine was altered to take the bar code scanner. At about the same time the Bristol Centre was helping TECHNICON with the development of the AUTO GROUPER C-16, and fortunately they decided on a laser reader of the same type for bar code identification. Thus there were three centres with the capability for reading bar codes on blood grouping machines and it became necessary to find someone to produce the bar code labels. There was only on~ printer in the UK who could produce labels to the required specification. To cut the costs of printing, and in the hope of avoiding a wide variation in codes, I invited representatives of centres interested in the problem to a meeting, where we set up what we called the Group of Six. This later became an official Working Party of the Regional Transfusion Directors.
Micromachined Mirrors provides an overview of the performance enhancements that will be realized by miniaturizing scanning mirrors like those used for laser printers and barcode scanners, and the newly enabled applications, including raster-scanning projection video displays and compact, high-speed fiber-optic components.
Micromachined scanning mirrors are interesting for a wide variety of applications because of their potential low cost, high speed, low power consumption, and reliability. These mirrors can offer significant advantages over macro-scale mirrors, but the fundamental limitations of scanning mirrors have not been widely discussed.
The progress of science during the past centuries has been in some measure energized by the development of new technologies. People are no more intelligent now than they were five centuries ago, or indeed five millenia ago. The differences are in the pool of past experience and the availability of means for manipulating the physical and mental environment. Until fairly recently, the development of new technologies in astronomy and geodesy has served primarily either to broaden the scope of phenomena that could be studied or to improve the precision with which one could examine already-studied phenomena. There seemed to be no likelihood that a situation could arise similar to that in particle physics, where the uncertainty principle indicates that the observation of the state of an object alters that state, affecting the observation. Indeed, we have not yet reached that point, but certain of the new techniques have introduced a degree of complication and inter- dependence perhaps not previously encountered in the macro- sciences. When observational capability is so fine that the data can be corrupted by the tidal motions of the instruments, for example, then there are a myriad of physical effects that must be considered in analyzing the data; the happy aspect of this is that the data can be used to study exactly these same effects. The complication does not, however, extend only to predictive computations against which the data are compared.
Developments in power electronics and digital control have made the rugged, low-cost, high-performance induction machine the popular choice of electric generator/motor in many industries. As the induction machine proves to be an efficient power solution for the flexible, distributed systems of the near future, the dynamic worldwide market continues to grow. It is imperative that engineers have a solid grasp of the complex issues of analysis and design associated with these devices.
The Induction Machines Design Handbook, Second Edition satisfies this need, providing a comprehensive, self-contained, and up-to-date reference on single- and three-phase induction machines in constant and variable speed applications. Picking up where the first edition left off, this book taps into the authors' considerable field experience to fortify and summarize the rich existing literature on the subject. Without drastically changing the effective logical structure and content of the original text, this second edition acknowledges notable theoretical and practical developments in the field that have occurred during the eight years since the first publication. It makes corrections and/or improvements to text, formulae, and figures.
New material includes:
Broad coverage of induction machines includes applications, principles and topologies, and materials, with numerical examples, analysis of transient behavior waveforms and digital simulations, and design sample cases. The authors address both standard and new subjects of induction machines in a way that will be both practically useful and inspirational for the future endeavors of professionals and students alike.
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