17,623 research outputs found
Wide temperature range electronic device with lead attachment
A electronic device including lead attachment structure which permits operation of the devices over a wide temperature range is reported. The device comprises a core conductor having a thin coating of metal thereon whereby only a limited amount of coating material is available to form an alloy which bonds the core conductor to the device electrode, the electrode composition thus being affected only in the region adjacent to the lead
Motor brush wear measured with strain gages
Balanced bridge circuit, supplied with low-voltage direct current and connected to a readout device, measures remaining brush material, rate of brush wear, armature runout, and brush signature
Confirmation of the identification and establishment of the South American slipper limpet Crepipatella dilatata (Lamark 1822) (Caenogastropoda: Calyptraeidae) in Northern Spain
Schooling and Health: The Cigarette Connection
Numerous studies by economists during the past decade have revealed a large, statistically significant correlation between health and years of schooling after controlling for differences in income and other variables. Cigarette smoking is a likely intervening variable because of the strong effect of smoking on morbidity and mortality, and because there is a strong negative correlation between smoking and years of schooling -- at least at high school levels and above. This paper tests the hypothesis that schooling causes differences in smoking behavior. We use retrospective smoking histories of 1,183 white, non-Hispanic men and women who had completed 12 to 18 years of schooling. The data were collected in 1979 by the Stanford University Heart Disease Prevention Program from randomly selected households in four small California cities. The most striking result is that the negative relation between schooling and smoking observed at age 24 is accounted for by differences in smoking behavior present at age 17, when all subjects were still in approximately the same grade. We conclude that additional years of schooling cannot be the cause of differential smoking behavior; one or more "third variables" must cause changes in both smoking and schooling. Analysis of smoking by cohort reveals that the schooling-smoking correlation developed only after the health consequences of smoking became widely known; it has remained strong even in the most recent cohorts. This implies that the mechanism behind the schooling-smoking correlation may also give rise to the schooling-health correlation.
The geometry and physical properties of exhaust clouds generated during the static firing of S-1C and S-2 rocket engines
An experimental program was conducted during the static firing of the S-1C stage 13, 14, and 15 rocket engines and the S-2 stage 13, 14, and 15 rocket engines. The data compiled during the experimental program consisted of photographic recordings of the time-dependent growth and diffusion of the exhaust clouds, the collection of meteorological data in the ambient atmosphere, and the acquisition of data on the physical structure of the exhaust clouds which were obtained by flying instrumented aircraft through the clouds. A new technique was developed to verify the previous measurements of evaporation and entrainment of blast deflector cooling water into the cloud. The results of the experimental program indicate that at the lower altitudes the rocket exhaust cloud or plume closely resembles a free-jet type of flow. At the upper altitudes, where the cloud is approaching an equilibrium condition, structure is very similar to a natural cumulus cloud
Investment Decisions and Emissions Reductions : Results from Experiments in Emissions Trading
Emissions trading is an important regulatory tool in environmental policy making. Unfortunately the effectiveness of these regulations is difficult to measure in the field due to the unavailability of appropriate data. In contrast, experiments in the laboratory can provide guidance to regulators and legislatures about the performance of different market features in emission trading programs. This paper reports on the implementation of three different institutional designs, and presents experimental results investigating important features of emissions trading regimes: the ability to make investments in emissions abatement, ability to bank allowances and a declining emissions cap, both with and without uncertainty. These features are observed in virtually all existing air pollution emissions trading programs currently in place and will almost certainly be part of future applications. Like previous experimental studies of emissions trading, this paper shows that the efficiency gains expected from economic theory emerge observationally. We also show reduced efficiency when permits are bankable due to over-banking and when investments in emissions abatement are possible due to overinvesting. These tendencies do not worsen, however, when emissions caps decline.Emissions Trading, Investment in Abatement, Banking, Laboratory Experiments
Survey of multi-function display and control technology
The NASA orbiter spacecraft incorporates a complex array of systems, displays and controls. The incorporation of discrete dedicated controls into a multi-function display and control system (MFDCS) offers the potential for savings in weight, power, panel space and crew training time. The technology applicable to the development of a MFDCS for orbiter application is surveyed. Technology thought to be applicable presently or in the next five years is highlighted. Areas discussed include display media, data handling and processing, controls and operator interactions and the human factors considerations which are involved in a MFDCS design. Several examples of applicable MFDCS technology are described
Superorbital Period in the High Mass X-ray Binary 2S 0114+650
We report the detection of a superorbital period in the high-mass X-ray
binary 2S 0114+650. Analyses of data from the Rossi X-ray Timing Explorer
(RXTE) All-Sky Monitor (ASM) from 1996 January 5 to 2004 August 25 reveal a
superorbital period of 30.7 +/- 0.1 d, in addition to confirming the previously
reported neutron star spin period of 2.7 h and the binary orbital period of
11.6 d. It is unclear if the superorbital period can be ascribed to the
precession of a warped accretion disc in the system.Comment: 5 pages, 5 figures, submitted to MNRAS 27th January 2005. Manuscript
expanded to include discussion of evolution of periods, and hardness ratio
variability. Number of figures increased from 5 to 9. Accepted for
publication 19th December 200
Development of preliminary design concept for a multifunction display and control system for the Orbiter crew station. Task 4: Design concept recommendation
Application of multifunction display and control systems to the NASA Orbiter spacecraft offers the potential for reducing crew workload and improving the presentation of system status and operational data to the crew. A design concept is presented for the application of a multifunction display and control system (MFDCS) to the Orbital Maneuvering System and Electrical Power Distribution and Control System on the Orbiter spacecraft. The MFDCS would provide the capability for automation of procedures, fault prioritization and software reconfiguration of the MFDCS data base. The MFDCS would operate as a stand-alone processor to minimize the impact on the current Orbiter software. Supervisory crew command of all current functions would be retained through the use of several operating modes in the system. Both the design concept and the processes followed in defining the concept are described
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