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The exchange of the energy storage unit from an electric vehicle is considered an alternative to in-vehicle battery charging. If the exchange process is mechanically assisted or automated, the exchange can potentially be accomplished in much less time than that required for in-vehicle charging. Many means for accomplishing battery exchange have been proposed or attempted, with various degrees of success, from the late 1800's through the present. In recent years, battery exchange methods have not been embraced by the electric vehicle industry, in deference to fast in-vehicle battery charging. Only a small number of semi-automated mechanizations have actually been demonstrated. The history of electric vehicle battery exchange is reviewed, focusing on innovations and technical lessons learned. Design and deployment considerations are identified for battery exchange in general, and specific embodiments thereof. A technical comparison with fast charging is presented.

The limited energy storage and long recharge time of electric vehicle batteries have motivated several alternatives to in-vehicle slow charging. Solutions generally fall into three categories: (1) fast charging, in which batteries are charged in-vehicle at an accelerated rate, (2) battery material reloading or refueling, in which the energy-carrying elements of the battery are physically replaced or replenished, and (3) battery interchange, involving the complete exchange of the battery pack, usually with the aid of some semi-automated mechanism. Among these options, the last, battery interchange, has tended to receive the least industry attention, but has been an expansive topic of invention and novel deployment.

This paper reviews the findings of a study commissioned by the California Department of Transportation to evaluate the potential of infrared and passive millimeter-wave imaging technologies for traffic surveillance and automated detection. Images formed from radiation at infrared and millimeter wavelengths are characterized by fundamentally different information compared with visible-spectrum images, and generally improved ability to penetrate obscured atmospheres such as fog or dust. Ten examples of commercially available infrared (IR) imaging technologies and one experimental passive millimeter-wave (MMW) radiometric imaging apparatus were evaluated with respect to the specific requirements of highway monitoring and traffic management. A suite of traffic images and performance-related test data were acquired for each imaging system over a range of traffic and environmental conditions.

Closed circuit television (CCTV) systems deployed on roadway networks are believed to be among the best mechanisms for providing useful, reliable information for effective traffic management. Video images may be displayed and viewed directly by traffic management personnel for surveillance purposes, or may be processed electronically for detection of traffic metrics such as average vehicle speed, flow volume, and traffic density. This paper summarizes the current state-of-the art in video imaging and video signal processing technology for traffic surveillance and electronic detection. Technical considerations relevant to the selection of video cameras and computer vision hardware and software for this application are reviewed. Applicable standards are identified, and evaluation criteria and test procedures are described. Commercially available monochrome and color video cameras are examined with respect to sited criteria.