49,647 research outputs found
Questioning the Quantitative Imperative: Decision Aids, Prevention, and the Ethics of Disclosure
Patients should not always receive hard data about the risks and benefits of a medical intervention. That information should always be available to patients who expressly ask for it, but it should be part of standard disclosure only sometimes, and only for some patients. And even then, we need to think about how to offer it
Discounting a Surgical Risk: Data, Understanding, and Gist
Excerpt: A few days after the surgery, Ms. Reid came in for an emergency appointment with Dr. Feng. It was obvious that she was irate,but her voice could barely be heard above the noise of the clinic. "I thought you said this was rare," she said, shaking a printout of a journal article on the subject. My recurrent laryngeal nerve was injured. I'm a teacher, and I have children! I need my voice. I would have never done the surgery if I knew there was a 4 percent risk that I would lose my voice!" Was Dr. Feng negligent in explaining the risks of surgery to Ms. Reid? Was she required to use precise percentages of risk
The requirements for batteries for electric vehicles
Analysis of automobile use patterns shows that the battery requirements for an urban car can be met by mid-term battery technology. The far-term technology potentially offers greater range but does not proportionately increase the usefulness of the vehicle. This suggests that emphasis should be shifted toward more modest energy density goals, if such a shift would ease technical problems and allow the use of lower cost materials and construction methods. A technology diffusion model indicates that the impact of the mid-term batteries by the year 2000 would be greater than that of the far-term batteries because of their earlier introduction and nearly equal market potential. From the standpoint of maximizing both the cumulative impact and the benefits derived in the year 2000, however, a strategy of early introduction of near-term and mid-term cars followed by the far-term vehicle would produce the optimum results
Batteries for storage of wind-generated energy
Cost effectiveness characteristics of conventional-, metal gas-, and high energy alkali metal-batteries for wind generated energy storage are considered. A lead-acid battery with a power density of 20 to 30 watt/hours per pound is good for about 1500 charge-discharge cycles at a cost of about $80 per kilowatt hour. A zinc-chlorine battery that stores chlorine as solid chlorine hydrate at temperatures below 10 C eliminates the need to handle gaseous chlorine; its raw material cost are low and inexpensive carbon can be used for the chlorine electrode. This system has the best chance to replace lead-acid. Exotic alkali metal batteries are deemed too costly at the present stage of development
A survey of classical Langmuir probe theory with applications to flowing ionized gases Interim report
Classical Langmuir probe theory with applications to flowing ionized gase
Propulsion system research and development for electric and hybrid vehicles
An approach to propulsion subsystem technology is presented. Various tests of component reliability are described to aid in the production of better quality vehicles. component characterization work is described to provide engineering data to manufacturers on component performance and on important component propulsion system interactions
Electric and hybrid vehicle system R/D
The work being done to characterize the level of current propulsion technology through component testing is described. Important interactions between the battery and the propulsion system will be discussed. Component development work, involving traction motors, motor controllers and transmissions are described and current results are presented. Studies of advanced electric and hybrid propulsion system studies are summarized and the status of propulsion system development work supported by the project is described. A strategy for fostering joint industry/government projects for commercialization of propulsion components and systems is described briefly
The Federal electric and hybrid vehicle program
The commercial development and use of electric and hybrid vehicles is discussed with respect to its application as a possible alternative transportation system. A market demonstration is described that seeks to place 10,000 electric hybrid vehicles into public and private sector demonstrations
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