Nickel Cadmium Charge Control Concepts

The design and testing of charge control concepts for several power systems is presented. The design of the CRAM charge control system for the SAS satellites and the design of the battery charge regulator for the AMPTE satellites is reviewed. Another charge control concept examined is for the OPEN program and its use of a microprocessor. The use of the voltage limiter is also discussed

YAG aerosol lidar

The Global Atmospheric Backscatter Experiment (GLOBE) Mission, using the NASA DC-8 aircraft platform, is designed to provide the magnitude and statistical distribution of atmospheric backscatter cross section at lidar operating wavelengths. This is a fundamental parameter required for the Doppler lidar proposed to be used on a spacecraft platform for global wind field measurements. The prime measurements will be made by a CO2 lidar instrument in the 9 to 10 micron range. These measurements will be complemented with the Goddard YAG Aerosol Lidar (YAL) data in two wavelengths, 0.532 and 1.06 micron, in the visible and near-infrared. The YAL, is being designed to utilize as much existing hardware, as feasible, to minimize cost and reduce implementation time. The laser, energy monitor, telescope and detector package will be mounted on an optical breadboard. The optical breadboard is mounted through isolation mounts between two low boy racks. The detector package will utilize a photomultiplier tube for the 0.532 micron channel and a silicon avalanche photo detector (APD) for the 1.06 micron channel

Small Gas Turbine Combustor Primary Zone Study

The combustion research program, small gas turbine combustor primary zone study is summarized. The basic elements of a design methodology program to obtain the maximum performance potential of small reverse-flow annular combustors is described. Three preferred combustion design approaches for internal flame stabilization patterns were selected. Design features are incorporated in the combustors to address the performance limiting problem areas associated with smaller annular combustors. Performance is predicted by using a 3-D aerodynamic/chemical kinetic elliptic flow analysis, initially developed by Garrett Corporation for the USARTL. It is shown that the analytical flow field predictive models provide a useful design tool for understanding the combustion performance of a small reverse flow annular combustor

Computer transformation of partial differential equations into any coordinate system

The use of tensors to provide a compact way of writing partial differential equations in a form valid in all coordinate systems is discussed. In order to find solutions to the equations with their boundary conditions they must be expressed in terms of the coordinate system under consideration. The process of arriving at these expressions from the tensor formulation was automated by a software system, TENSR. An allied system that analyzes the resulting expressions term by term and drops those that are negligible is also described

Exploding bridgewire detonator simulator

Tests indicate that electric detonator simulators of the exploding bridgewire type will not fire as a result of the application of a direct current power of one watt for 5 minutes. The detonator also will not fire if the protective gap fails and the firing stimulus is inadvertently applied

Better No Longer to Be

David Benatar argues that coming into existence is always a harm, and that – for all of us unfortunate enough to have come into existence – it would be better had we never come to be. We contend that if one accepts Benatar’s arguments for the asymmetry between the presence and absence of pleasure and pain, and the poor quality of life, one must also accept that suicide is preferable to continued existence, and that his view therefore implies both anti-natalism and pro-mortalism. This conclusion has been argued for before by Elizabeth Harman – she takes it that because Benatar claims that our lives are ‘awful’, it follows that ‘we would be better off to kill ourselves’. Though we agree with Harman’s conclusion, we think that her argument is too quick, and that Benatar’s arguments for non-pro-mortalism deserve more serious consideration than she gives them. We make our case using a tripartite structure. We start by examining the prima facie case for the claim that pro-mortalism follows from Benatar’s position, presenting his response to the contrary, and furthering the dialectic by showing that Benatar’s position is not just that coming into existence is a harm, but that existence itself is a harm. We then look to Benatar’s treatment of the Epicurean line, which is important for him as it undermines his anti-death argument for non-pro-mortalism. We demonstrate that he fails to address the concern that the Epicurean line raises, and that he cannot therefore use the harm of death as an argument for non-pro-mortalism. Finally, we turn to Benatar’s ro-life argument for non-pro-mortalism, built upon his notion of interests, and argue that while the interest in continued existence may indeed have moral relevance, it is almost always irrational. Given that neither Benatar’s anti-death nor pro-life arguments for non-pro-mortalism work, we conclude that pro-mortalism follows from his anti-natalism, As such, if it is better never to have been, then it is better no longer to be

Growth and claw regeneration of the stone crab, Menippe mercenaria

Savage, T. and J.R. Sullivan. 1978. Growth and Claw Regeneration of the Stone Crab, Menippe mercenaria. Fla. Mar. Res. Publ. No. 32.23 pp. Laboratory-maintained and feral crabs were observed for incremental carapace width and major and minor claw growth. Morphometric relationships for male and female carapace width against length and carapace width against major and minor claw sizes were derived. Only slopes of carapace width us. female major and male minor claws were not significantly different at the 95% confidence level. Feral normal male incremental growth exceeded that of normal females for all parameters. Normal laboratory females possessed greater average carapace width growth but less claw growth than did their male counterparts. All laboratory growth was more uniform but incrementally smaller than corresponding field growth. A hypothetical growth plot constructed from incremental growth of several crabs indicated ages at attainment of sexual maturity and legal size to be 10 and 30 months. A pictorial description of stone crab claw regeneration is presented. Minor claws realized greater regeneration after one and two molts (73.5% and 96.5% of pre-autotomized sizes) than did major claws (68.6% and 89.0%). Intermolt interval of laboratory crabs increased with larger carapace width sizes. Claw loss shortened or lengthened duration of the intermolt period depending upon whether the claw was removed shortly after a molt or later in the cycle. (Document has 27 pages.

Learning From Complexity: Effects Of Prior Accidents And Incidents On Airlines' Learning

Using data on accidents and incidents experienced by U.S. commercial airlines from 1983 to 1997, we investigated variation in firm learning by examining whether firms learn more from errors with heterogeneous or homogeneous causes. We measured learning by a reduction in airline accident and incident rates, while controlling for other factors related to accidents and incidents. Our results show that heterogeneity is generally better for learning, as prior heterogeneity in the causes of errors decreases subsequent accident rates, producing a deeper, broader search for causality than simple explanations like >blame the pilot.> The benefits of heterogeneity, however, apply mainly to specialist airlines. Generalist airlines learn, instead, from outside factors such as the experience of others and general improvements in technology. These results suggest a theory of learning across organizational forms: complex forms benefit from simple information, and simple forms benefit from complex information. The implications of our study for learning theories and work on organizational errors are discussed.Business Administratio