Refracting profiles and generalized holodiagrams

The recently developed concept of refracting profiles and that of refraction holodiagrams are combined so that the classical Abramson holodiagrams can be generalized taking into account a wider class of wave fronts and refraction at an interface, whenever regions of caustics are avoided. These holodiagrams are obtained as envelopes of specific families of Cartesian Ovals with an appropriate parametrization. Classical and reflecting holodiagrams are particular cases of this class. Several of the properties of the classical holodiagrams are shared by their richer generalized versionsComment: 12 pages, 7 figure

Clean Economy Rising: Manufacturing Powers Clean Energy in Ohio

Ohio has built upon its rich manufacturing legacy to become a leader in the production of wind, solar, and industrial energy efficiency technologies. Until recently, state and federal policies also spurred renewable energy projects throughout Ohio. Uncertainty over the future of these measures is dampening investment. This brief explores the drivers of Ohio's clean energy economy and the choices the state faces about its future competitiveness in the industry

The ALOHA SYSTEM

The report provides a status report and description of THE ALOHA SYSTEM research project at the University of Hawaii. THE ALOHA SYSTEM involves the analysis and construction of advanced methods of random access communications in large computer-communication systems. The existing ALOHA SYSTEM computer-communication network uses two 24,000 baud channels in the UHF band. The system employs message switching techniques similar to those of the ARPANET, in conjunction with a novel form of random access radio channel multiplexing. By means of these techniques the system has the capacity to accommodate several hundred active users of alphanumeric consoles on the two channels available. Each of these users can transmit and receive at a peak data rate of 24,000 baud although the average data rate of the users must of course be considerably less