C. J. Das Скачать все книги 2 Количество книг

The physical properties of ultrasound, particularly its highly directional beam behaviour, and its complex interactions with human tissues, have led to its becoming a vitally important tool in both investigative and interventional medicine, and one that still has much exciting potential. This new edition of a well-received book treats the phenomenon of ultrasound in the context of medical and biological applications, systematically discussing fundamental physical principles and concepts. Rather than focusing on earlier treatments, based largely on the simplifications of geometrical acoustics, this book examines concepts of wave acoustics, introducing them in the very first chapter. Practical implications of these concepts are explored, first the generation and nature of acoustic fields, and then their formal descriptions and measurement. Real tissues attenuate and scatter ultrasound in ways that have interesting relationships to their physical chemistry, and the book includes coverage of these topics. Physical Principles of Medical Ultrasonics also includes critical accounts and discussions of the wide variety of diagnostic and investigative applications of ultrasound that are now becoming available in medicine and biology. The book also encompasses the biophysics of ultrasound, its practical applications to therapeutic and surgical objectives, and its implications in questions of hazards to both patient and operator.

Up-to-date analysis methodologies and practical mitigation for a major electrical safety concern Arc Flash Hazard Analysis and Mitigation is the first book to focus specifically on arc flash hazards and provide the latest methodologies for its analysis as well as practical mitigation techniques. Consisting of sixteen chapters, this fully up-to-date handbook covers all aspects of arc flash hazard calculations and mitigation. It addresses the calculations of short circuits, protective relaying, and varied electrical systems configurations in electrical power systems. It also examines protection systems, including differential relays, arc flash sensing relays, protective relaying coordination, current transformer operation and saturation, and applications to major electrical equipment from the arc flash point of view. Current technologies and strategies for arc flash mitigation are explored. Using the methodology, analysis, and preventive measures discussed in the book, the arc flash hazard incident energy can be reduced to 8 cal/cm2 or less for the new and existing electrical distribution systems. This powerful resource: Features the most up-to-date arc flash analysis methodologies Presents arc flash hazard calculations in dc systems Supplies practical examples and case studies Provides end-of-chapter reviews and questions Includes a Foreword written by Lanny Floyd, a world-renowned leader in electrical safety who is DuPont's Principal Consultant on Electrical Safety and Technology Arc Flash Hazard Analysis and Mitigation is a must-have guide for electrical engineers engaged in design, operation, and maintenance, consulting engineers, facility managers, and safety professionals.