2,892 research outputs found
Telemetry downlink interfaces and level-zero processing
The technical areas being investigated are as follows: (1) processing of space to ground data frames; (2) parallel architecture performance studies; and (3) parallel programming techniques. Additionally, the University administrative details and the technical liaison between New Mexico State University and Goddard Space Flight Center are addressed
Multi-Market Trading for Cooperative Resource Management: An Application to Water Pollution and Fisheries
Increasingly, environmental problems are recognized to involve linkages across multiple environmental variables (e.g., pollution and a fishery). Prior work on managing these complex, linked systems generally focuses on efficiency rather than implementation. However, implementation is important and will generally involve changing human behaviors within the multiple economic sectors that impact upon the multiple environmental variables. Tradable permit markets are generally seen as a coordinating mechanism, within a particular regulated sector, that enhances efficiency by incentivizing agents to respond to behavioral choices of others within the sector. However, prior work stops short of coordinating behaviors across multiple sectors for cases where society benefits from regulation in both sectors and one sector harms the other. We analyze a multi-sector permit market involving both the externality-generating sector and the affected sector. This multi-sector market provides a mechanism for agents in one sector to respond to environmental behaviors made within the other sector. Moreover, unlike traditional permit markets in which the regulated externality sector incurs only costs, we show that the multi-sector market generates efficiency gains that may be redistributed using appropriate allocations of initial endowments. Accordingly, the multi-sector market may generate gains that benefit both sectors, resulting in a win-win outcome for both sectors. We use a simple example of a polluted fishery to illustrate the approach.Permit trading, fisheries, pollution, Shapley values, bioeconomics, Environmental Economics and Policy, Resource /Energy Economics and Policy,
Test report: Low cost access and efficient use of TDRSS
In order to develop new ways to increase the number of users taking advantage of NASA's Space Network for space-to-ground communications links, researchers at New Mexico State University (NMSU) developed a technique for using non-gimballed antennas for accessing a Tracking and Data Relay Satellite (TDRS) within the Space Network (SN). This concept would allow spin-stabilized satellites to access one of the TDRS spacecraft in the SN constellation as the user satellite sweeps past the TDRS position as the satellite approaches either its ascending or descending node if this node is relatively close to the TDRS subsatellite point. ne research team from NMSU developing this concept proposed to NASA the use of the Extreme Ultra Violet Explorer (EUVE) to test this concept on orbit. EUVE differs from the desired satellite configuration in that EUVE has a relatively high-gain parabolic antenna and, most importantly, EUVE has an inertially-stabilized attitude control system while the concept to be tested was for a spin-stabilized satellite. We believed that these limitations would not affect the basic proof-of-concept test we were trying to achieve. With the approval and coordination of NASA, a total of six satellite passes through the West TDRS were requested and the necessary equipment configured for data collection at the Second TDRS Ground Terminal (STGT), also known as Danzante, at the White Sands Complex
The Coordination and Design of Point-Nonpoint Trading Programs and Agri-Environmental Policies
Agricultural agencies have long offered agri-environmental payments that are inadequate to achieve water quality goals, and many state water quality agencies are considering point-nonpoint trading to achieve the needed pollution reductions. This analysis considers both targeted and nontargeted agrienvironmental payment schemes, along with a trading program which is not spatially targeted. The degree of improved performance among these policies is found to depend on whether the programs are coordinated or not, whether double-dipping (i.e., when farmers are paid twice-once by each program-to undertake particular pollution control actions) is allowed, and whether the agri-environmental payments are targeted. Under coordination, efficiency gains only occur with double-dipping, so that both programs jointly influence farmers' marginal decisions. Without coordination, doubledipping may increase or decrease efficiency, depending on how the agri-environmental policy is targeted. Finally, double-dipping may not solely benefit farmers, but can result in a transfer of agricultural subsidies to point sources.Environmental Economics and Policy,
Improving the Efficiency and Effectiveness of Agri-environmental Policies for the Chesapeake Bay
Water Quality, Nonpoint Source Pollution, Policy Instrument, Chesapeake Bay, Environmental Economics and Policy, Resource /Energy Economics and Policy, Q25, Q58,
Neutron Energy Effects on Asteroid Deflection
In the future, a hazardous asteroid will find itself on a collision course with Earth. It is an inevitability; the question is not if, but when. For asteroids of moderate size or larger, a nuclear device is one of humanity\u27s only technologies capable of mitigating this threat via deflection on a timescale of less than a decade. This work examined how changing the output neutron energy from a nuclear device detonation affects asteroid deflection. The notional asteroid target was 300 meters in diameter and composed of silicon dioxide at a bulk density of 1.855 g/cm3. To calculate the energy deposition in the asteroid that results from a neutron source, the Monte Carlo radiation-transport code, MCNP6.2, was applied. MCNP6.2 simulations were performed for neutrons of various energies radiating towards the asteroid surface. The neutron energy was found to have an impact in terms of 1) the energy deposition spatial profile, and 2) the energy coupling efficiency. To model the mechanical response of the asteroid due to a spatially-varying energy deposition, the hydrodynamics code, ALE3D, was employed. The energy deposition outputs from MCNP6.2 served as inputs into the model representation of the asteroid in ALE3D. The momentum impulse imparted onto the asteroid body due to rapidly- evolving melted and/or vaporized blow-off ejecta was quantified. From this, the asteroid velocity change, or δV , was determined for two different neutron yields (50 kt and 1 Mt) and for two different source neutron energies (14.1 MeV from fusion and 1 MeV from fission). Underexplored in literature, the distribution of deposited energy and the energy coupling were both found to affect the asteroid deflection. The magnitude of energy deposition, as determined by the neutron energy and the coupling, generally appears to be the more significant factor
THE DESIGN AND COMPARATIVE ECONOMIC PERFORMANCE OF ALTERNATIVE SECOND-BEST POINT/NONPOINT TRADING MARKETS
There is considerable interest in the use of pollution trading between point and nonpoint sources to improve the cost-effectiveness of water pollution control, but little literature to guide the design of trading systems involving nonpoint sources. We explore the design of two types of trading systems that would allow trading among and between point and nonpoint sources.Environmental Economics and Policy,
THE VALUE OF ECOLOGICAL AND ECONOMIC INFORMATION IN WATER QUALITY MANAGEMENT
Replaced with revised version of paper 08/25/03.Environmental Economics and Policy,
Asymptotic Dynamics in Quantum Field Theory
A crucial element of scattering theory and the LSZ reduction formula is the
assumption that the coupling vanishes at large times. This is known not to hold
for the theories of the Standard Model and in general such asymptotic dynamics
is not well understood. We give a description of asymptotic dynamics in field
theories which incorporates the important features of weak convergence and
physical boundary conditions. Applications to theories with three and four
point interactions are presented and the results are shown to be completely
consistent with the results of perturbation theory.Comment: 18 pages, 3 figure
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