Science museums have paradoxes at their core. They must be accessible and fun while representing increasingly complex science. They must be both historic and contemporary. Their exhibits attract millions, but most of their objects remain in deep storage, seldom seen. This book delves into these conflicts, revealing the secret lives of science curators; where science objects com...(展开全部)

在准备本书第6版时，我想将一些对电力系统有较大影响的新内容介绍给大家，其中有以下5部分内容。 第13章、12.23～12.26节介绍了双馈感应电机的原理与特性。该电机的调速可通过在定子加固定频率交流电，而在转子通入可变频率交流电来实现，故名为“双馈”。双馈电机原来用作变速电动机来驱动大型水泵等负载，现在，该电机在风力发电中作为双馈发电动机使用。由于风力发电的重要性，有必要在本书中介绍这种特殊的电机。 第21章、21.45～21.51节对PWM的相关内容作了重要的修改，增加了新的内容及图片。 第23章介绍了几种电动机调速的电子控制方法。23.31～23.40节特别介绍了直接转矩控制（DTC）方法，与应用PWM及矢量控制方法不用，DTC使用了砰砰控制法，其对速度及转矩的控制与其他方法不同，该章根据感应电机原理，对此做了直观的分析。 第24章、24...(展开全部)

“Rich in dexterous innuendo, laugh-out-loud humor and illuminating fact. It’s compulsively readable.” — Los Angeles Times Book Review The best-selling author of Stiff turns her outrageous curiosity and insight on the most alluring scientific subject of all: sex. 16 illustrations

Museums are at a critical moment in their history. In order to ensure survival into the next century, museums and galleries must demonstrate their social relevance and use. This means developing their public service functions through becoming more knowledgeable about the needs of their visitors and more adept at providing enjoyable and worthwhile experiences. Museums and Their...(展开全部)

Questions on the origins and meaning of dreams are as old as humankind, and as confounding and exciting today as when nineteenth-century scientists first attempted to unravel them. Why do we dream? Do dreams hold psychological meaning or are they merely the reflection of random brain activity? What purpose do dreams serve? When Brains Dream addresses these core questions about ...(展开全部)

Told in rhyming text, Excavator, Bulldozer, Crane Truck, Dump Truck, and Cement Mixer will all need to work together as they tackle their biggest job yet--a massive building.

Herve This (pronounced "Teess") is an internationally renowned chemist, a popular French television personality, a bestselling cookbook author, a longtime collaborator with the famed French chef Pierre Gagnaire, and the only person to hold a doctorate in molecular gastronomy, a cutting-edge field he pioneered. Bringing the instruments and experimental techniques of the laborato...(展开全部)

Herve This (pronounced "Teess") is an internationally renowned chemist, a popular French television personality, a bestselling cookbook author, a longtime collaborator with the famed French chef Pierre Gagnaire, and the only person to hold a doctorate in molecular gastronomy, a cutting-edge field he pioneered. Bringing the instruments and experimental techniques of the laborato...(展开全部)

Men, Machines, and Modern Times, though ultimately concerned with a positive alternative to an Orwellian 1984, offers an entertaining series of historical accounts taken from the nineteenth century to highlight a main theme: the nature of technological change, the fission brought about in society by such change, and society's reaction to that change.Beginning with a remarkable ...(展开全部)

Man has within a single generation found himself sharing the world with a strange new species: the computers and computer-like machines. Neither history, nor philosophy, nor common sense will tell us how these machines will affect us, for they do not do "work" as did machines of the Industrial Revolution. Instead of dealing with materials or energy, we are told that they handle...(展开全部)