1,452 research outputs found
Air Force space power technology program
The military spacecraft power subsystem design requirements, developments goals, and planned technology efforts are summarized. The mission drivers of performance (weight and volume), hardening (survivability), autonomy, reliability, and miniaturization influence space mission effectiveness are outlined. The anticipated performance versus power level trends for reactor static conversion systems are illustrated. A conceptual design for a space based radar system is also given
Military needs for orbital power
Results of the DoD/ERDA (now Department of Energy) Space Power Study completed in October 1977 are presented. The major new thrust of Air Force Advanced Technology Plans center on the development of military solar power systems which will extend capabilities to the 10 - 50 KW sub e power range for new classes of missions while maintaining technology applicability to the 0.5 - 10 KW sub e present mission class. The status of FY78 efforts for Project 682J (Air Force Space Power Advanced Development Program) are reported. Project 682J is divided into the following tasks: (1) high efficiency solar panel; (2) nickel-hydrogen battery; (3) gallium arsenide solar concentrator hardness study; and (4) new-start nuclear dynamic power system applications/integration study
Future Military Spacecraft Power Systems
During the past several years, a number of military space mission studies have concluded with interesting new information on the future needs and directions of military spacecraft power systems. In all cases, the trend to higher power level, for continuous as well as pulsed requirements, is clear. Although precise dates are impossible to define at this time, military spacecraft of the next twenty years will require steady state electrical power in the range of 10 to 100 kilowatts with pulsing capabilities in the megawatt region. As such, the major thrust of the DOD space power technology program focuses on the development of military power systems which will extend capabilities to the upper end of these ranges while maintaining technology applicability to the current lower level power requirements. Because of assumed delivery and orbital transfer limitations, the weight and volume of these high power systems must be kept as low as possible without sacrificing the reliability and lifetime of the power systems. These constraints necessitate the early application of very advanced solar/array battery systems and possibly nuclear reactor power supplies. As usual, the survivability of the power systems to natural and imposed radiation environments remains a concern for military systems. In addition to the above, the need for spacecraft system autonomy is being emphasized and programs to enhance the fault-tolerance and energy management of future military power systems are being initiated
An Agent Based Model for the Simulation of Transport Demand and Land Use
Agent based modelling has emerged as a promising tool to provide planners with insights on social behaviour and
the interdependencies characterising urban system, particularly with respect to transport and infrastructure planning.
This paper presents an agent based model for the simulation of land use and transport demand of an urban area
of Sydney, Australia. Each individual in the model has a travel diary which comprises a sequence of trips the person
makes in a representative day as well as trip attributes such as travel mode, trip purpose, and departure time.
Individuals are associated with each other by their household relationship, which helps define the interdependencies
of their travel diary and constrains their mode choice. This allows the model to not only realistically reproduce how
the current population uses existing transport infrastructure but more importantly provide comprehensive insight into
future transport demands. The router of the traffic micro-simulator TRANSIMS is incorporated in the model to inform
the actual travel time of each trip and changes of traffic density on the road network. Simulation results show very
good agreement with survey data in terms of the distribution of trips done by transport modes and by trip purposes,
as well as the traffic density along the main road in the study area
Exact results and scaling properties of small-world networks
We study the distribution function for minimal paths in small-world networks.
Using properties of this distribution function, we derive analytic results
which greatly simplify the numerical calculation of the average minimal
distance, , and its variance, . We also discuss the
scaling properties of the distribution function. Finally, we study the limit of
large system sizes and obtain some analytic results.Comment: RevTeX, 4 pages, 5 figures included. Minor corrections and addition
Petition for a Writ of Certiorari to the United States Court of Appeals for the Ninth Circuit, Jensen v. EXC, Inc.
The petitioners argue:
1) Supervisory Review is Needed Because the District Court and the Ninth Circuit Automatically Aligned U.S. Highway 160 with Alienated, Non-Indian Fee Land, Ignoring this Court’s Context-Specific, Multifactor Methodology for Determining the Status of Reservation Roadways for Tribal Jurisdictional Purposes.
2) Supervisory Review is Also Necessary Because Both Lower Courts Refused to Apply Supreme Court Precedents Governing Whether an Indian Tribe Retains Treaty-Based Authority over the Conduct of Nonmembers on a Tribe’s Reservation, Effecting an Impermissible Judicial Abrogation of the Navajo Nation’s Congressionally Confirmed, Treaty-Based Jurisdiction in This Case.
3) Supervisory Review is Further Needed Because Both Lower Courts’ Denial of the Navajo Nation’s Retained Inherent Sovereignty over the Tour Bus/Auto Collision Conflicts with This Court’s Precedents for Proper Application of the Montana Exceptions
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