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11.
A tactical system designed to inspect and diagnose malfunctions in all army tactical vehicles including jeeps, trucks, and tanks is known as Ready Multipurpose Automatic Inspection and Diagnostic System (READYMAIDS). The laboratory model developed to prove the feasibility of design is discussed together with design problems such as instrumenting a vehicle without modifications. The system uses a small digital computer in addition to switching, measurement, and loading devices. These devices are integrated into a small transportable unit. Results to date, problem areas, and possible solutions are described.  相似文献   
12.
Lifting the veil on CORONA   总被引:1,自引:0,他引:1  
Albert D. Wheelon   《Space Policy》1995,11(4):249-260
Information on some of the USA's military space reconnaisance programs has recently been declassified, allowing details of the nature of the technology used and its capabilities to be publicly aired. In this article, a personal account of the situation leading up to the creation of the USA's first military satellite system — named CORONA — is provided, along with discussion of its design, development and program management. CORONA's enormous impact on intelligence gathering is assessed; lessons learned from the program are presented.  相似文献   
13.
Simulation of light curve effects in Algol systems that are near contact or that may evolve into contact requires a different model than the tri-axial ellipsoid used in many current studies. A new light synthesis optimization program, based on the Roche model, satisfies the model requirements and determines system parameters with excellent accuracy, given a sufficiently large set of observations. A widely used criterion for stopping iterative solutions is inadequate. A working criterion is proposed as a replacement.  相似文献   
14.
This study presents two experiments that examine howindividuals learn relative directions betweenlandmarks in a desktop virtual environment. Subjectswere presented snapshot images of different virtualenvironments containing distinguishing landmarks anda road network. Following the presentation of eachvirtual environment, subjects were given a relativedirection test. The relative direction test involvedindicating the direction of hidden landmarks fromdifferent vantage points in the environment. Half ofthese vantage points were presented during thelearning phase, while the other half were novel.Results showed that subjects learned relativedirections between landmarks equally well when sceneswere presented in either a sequential or random order.Furthermore, viewing a configuration of landmarks ina desktop virtual environment from multipleperspectives produced a viewpoint dependentrepresentation in memory. Subjects had significantlygreater response times for new viewing perspectives,as compared to previously viewed scenes. Thisviewpoint dependent representation of the environmentpersisted despite learning under conditions ofspatio-temporal discontinuity and changes to anenvironmental frame of reference.  相似文献   
15.
Although initially we will know virtually nothing about any society that our microwave search detects, in all likelihood their society will be far older than ours. It will have evolved mechanisms to ensure longevity. A pessimistic hypothesis would lead us to expect a powerful, aggressive and self-serving society that has vanquished all challengers. If this hypothesis were true, a response by us to their signal could be dangerous. An optimistic hypothesis, that it is the peaceful societies that survive, would lead us to expect a benign or even friendly civilization. If this second hypothesis were true, our response would gratify their scientific curiosity and perhaps lead to a useful exchange of information. Convergent evidence from the quantitative analyses of long-term historical trends and computer modeling support the optimistic hypothesis. Although not conclusive, this analysis suggests that revealing our presence in the Universe is a low risk activity.  相似文献   
16.
Space Science Reviews -  相似文献   
17.
Flying Laptop is the first small satellite developed by the Institute of Space Systems at the Universität Stuttgart. It is a test bed for an on-board computer with a reconfigurable, redundant and self-controlling high computational ability based on the field programmable gate arrays (FPGAs). This Technical Note presents the operational concept and the on-board payload data processing of the satellite. The designed operational concept of Flying Laptop enables the achievement of mission goals such as technical demonstration, scientific Earth observation, and the payload data processing methods. All these capabilities expand its scientific usage and enable new possibilities for real-time applications. Its hierarchical architecture of the operational modes of subsystems and modules are developed in a state-machine diagram and tested by means of MathWorks Simulink-/Stateflow Toolbox. Furthermore, the concept of the on-board payload data processing and its implementation and possible applications are described.  相似文献   
18.
Kelly T  Albert T  Levin GM 《Acta Astronautica》2001,48(5-12):809-815
The U.S. Congress has maintained an intense interest in the ISS program since its inception. In the Appropriations Act of 1997, the Senate of the United States included language directing National Aeronautics and Space Administration (NASA) to have the National Research Council (NRC) under take a study that evaluates the engineering challenges posed by extravehicular activity (EVA) requirements, United States and non-United States space launch requirements, the potential need to upgrade or replace equipment and components after Assembly Complete, and the requirement to decommission and disassemble the facility. NASA and the NRC decided the focus should be on the anticipated challenges in the continuous operation and maintenance of the ISS after assembly of the on-orbit facility has been completed. This would encompass the operational years, from late 2004 (if the current schedule holds) to 2020-2025. This executive summary overviews the results of this NRC study. It focuses on the U.S. operation of the ISS after Assembly Complete, including cooperative efforts by the United States and Russia. The paper summarizes the primary findings and recommendations in each of the areas considered during this two-year NRC study.  相似文献   
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