3,772 research outputs found
Turbopump thermodynamic cooling
System for cooling turbopumps used in cryogenic fluid storage facilities is described. Technique uses thermodynamic propellant vent to intercept pump heat at desired conditions. Cooling system uses hydrogen from outside source or residual hydrogen from cryogenic storage tank
Space shuttle low pressure auxiliary propulsion subsystem design definition Subtask B report
Space shuttle low pressure, hydrogen oxygen auxiliary propulsion subsystem preliminary desig
Systems Approach to the Concept of Environment
Author Institution: Department of Zoology and Institute of Ecology, University of GeorgiaA systems theory of environment formulates causal interactions between things, including organisms, and their environments in terms of four system theoretical abstract objects. Creaons receive stimuli and implicitly create input environments. Genons react to received causes and generate potential output environments as effects. A holon represents the combined input-output model of an entity consisting of a creaon and a genon. An environ is a creaon and its corresponding input environment, or a genon and its related output environment. The theory is presented in terms of three propositions that: (1) recognize two distinct environments (input and output) associated with things, (2) establish things and their environments as units (environs) to be taken together, and (3) partition systems into input and output environs associated with intrasystem creaons and genons, respectively
Species diversity in net phytoplankton of Raritan Bay
The annual diversity cycle in Raritan Bay net phytoplankton is described, using entropyrelated diversity indices. A theory of diversity change during succession is developed. Mean diversity levels in the estuary increased downbay in association with diminishing pollution, and the spatial pattern was strikingly related to general patterns of water mass circulation
Synoptic comparison of seston loads in the Rappahannock, York and James Rivers
This report summarizes data obtained during summer, 1962 on suspended solids profiles at Hog House Bar (Rappahannock, directly out from Urbanna Creek to 30 ft depth), the productivity buoy (York, 30 ft) and Wreck Shoal (James, adjacent to buoy 12 at edge of channel, 30 ft). Water samples obtained the same day from the three stations at s, 2 (ft), 61 10, 14, 18, 22, 26, B were analyzed for total, organic and inorganic seston by the gravimetric procedure described in VIMS Special Scientific Report No. 20 (1961). Temperature, chlorinity and extinction coefficient profiles were recorded, as well as Sand B dissolved oxygen
Dry electrodes for physiological monitoring
Subject preparation and application of sprayed dry electrodes for physiological monitorin
Method and apparatus for attaching physiological monitoring electrodes Patent
Adhesive spray process for attaching biomedical skin electrode
Government financial support for civil aircraft research, technology and development in four European countries and the United States
Data on the levels of government financial support for civil aircraft airframe and engine (CAAE) research and technology (R&T) in the United States and Europe (United Kingdom, West Germany, France and The Netherlands) and means of comparing these levels are provided. Data are presented for the years 1974-1977. European R&T expenditure data were obtained through visits to each of the four European countries, to the Washington office of the European Communities, and by a search of applicable literature. CAAE R&T expenditure data for the United States were obtained from NASA and Federal Aviation Administration (FAA)
Girls in IT: How to develop talent and leverage support
The objectives of this panel are to inform the audience about national and regional initiatives developed by the National Center for Women & Information Technology (NCWIT) to reach out to middle and high school girls; learn from promising experiences in which the panelists have been directly involved; and discuss venues to scale and sustain efforts to increase women\u27s participation in technology careers. Panelists will describe their particular experiences, and discuss ways to utilize the Aspirations in Computing program to increase enrollment and retention of females in computing. A minimum of 30 minutes will be set aside for question and answer
Functional Integration of Ecological Networks through Pathway Proliferation
Large-scale structural patterns commonly occur in network models of complex
systems including a skewed node degree distribution and small-world topology.
These patterns suggest common organizational constraints and similar functional
consequences. Here, we investigate a structural pattern termed pathway
proliferation. Previous research enumerating pathways that link species
determined that as pathway length increases, the number of pathways tends to
increase without bound. We hypothesize that this pathway proliferation
influences the flow of energy, matter, and information in ecosystems. In this
paper, we clarify the pathway proliferation concept, introduce a measure of the
node--node proliferation rate, describe factors influencing the rate, and
characterize it in 17 large empirical food-webs. During this investigation, we
uncovered a modular organization within these systems. Over half of the
food-webs were composed of one or more subgroups that were strongly connected
internally, but weakly connected to the rest of the system. Further, these
modules had distinct proliferation rates. We conclude that pathway
proliferation in ecological networks reveals subgroups of species that will be
functionally integrated through cyclic indirect effects.Comment: 29 pages, 2 figures, 3 tables, Submitted to Journal of Theoretical
Biolog
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