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31.
The design of the CAPE I satellite was underway for approximately three years. This interdisciplinary project incorporates electrical, mechanical, and aerospace engineering, as well as computer science and physics. The project hoped to teach students how to design, develop, and maintain a lower Earth orbiting satellite. This satellite was delivered to San Luis Obispo, California, December 5, 2006, where it passed the final integration test in order to qualify for launch. After qualification, the satellite was loaded into the poly-picosatellite orbital deployer or P-POD, which is the deployment system for the satellite. The P-POD holds three CubeSats. Once all three satellites were integrated, it was delivered to Kazakhstan and loaded into the DNEPR Russian Rocket on March 17, 2007. After a few delays, the rocket was launched on April 17,2007. The team is currently monitoring and decoding the CW beacons transmitted by the satellite. The project was broken into several subsystems including mechanical, communications, control and data handling, and power. Each of the systems proved to have their own unique challenges. Being that the majority of the team was electrical engineering students, the mechanical subsystem presented the most difficulty. There is currently a design in progress for the next satellite project, CAPE II. This new satellite will attempt a new benchmark by incorporating more advanced technologies than CAPE I and include other campus entities such as The Wetlands Research Center. The team hopes to deploy buoys into the Gulf of Mexico that will communicate to the CAPE 11 satellite in space and then send data to the ground station at the University. This data will include subjects such as coastal erosion, water temperatures, and drift currents throughout the Gulf. With this data, we can give other organizations the information obtained for their use as well.  相似文献   
32.
The divergence of horizontal radiation in vegetation canopies is generally considered to be of negligible consequence in algorithms designed for the physically-based interpretation of space borne observations. However, non-zero horizontal radiation balances are likely to occur if the internal variability of a vegetation target and the typical distances that photons may travel horizontally within such three-dimensional (3-D) media extend to spatial scales that are similar to or larger than those of the nominal footprint of the measuring sensor. Detailed radiative transfer simulations in 3-D coniferous forest environments are presented to document the typical distances that photons may travel in such media, and to quantify the impact that the resulting net horizontal fluxes may have with respect to the local and domain-averaged canopy reflectance. Based on these simulations it is possible to identify a fine spatial resolution limit beyond which pixel-based interpretations of remote sensing data over tall forested areas should be avoided because the horizontal radiation transport at the surface may contribute to 10% or more of the measured reflectance signature of the target pixel.  相似文献   
33.
Toward a global space exploration program: A stepping stone approach   总被引:1,自引:0,他引:1  
In response to the growing importance of space exploration in future planning, the Committee on Space Research (COSPAR) Panel on Exploration (PEX) was chartered to provide independent scientific advice to support the development of exploration programs and to safeguard the potential scientific assets of solar system objects. In this report, PEX elaborates a stepwise approach to achieve a new level of space cooperation that can help develop world-wide capabilities in space science and exploration and support a transition that will lead to a global space exploration program. The proposed stepping stones are intended to transcend cross-cultural barriers, leading to the development of technical interfaces and shared legal frameworks and fostering coordination and cooperation on a broad front. Input for this report was drawn from expertise provided by COSPAR Associates within the international community and via the contacts they maintain in various scientific entities. The report provides a summary and synthesis of science roadmaps and recommendations for planetary exploration produced by many national and international working groups, aiming to encourage and exploit synergies among similar programs. While science and technology represent the core and, often, the drivers for space exploration, several other disciplines and their stakeholders (Earth science, space law, and others) should be more robustly interlinked and involved than they have been to date. The report argues that a shared vision is crucial to this linkage, and to providing a direction that enables new countries and stakeholders to join and engage in the overall space exploration effort. Building a basic space technology capacity within a wider range of countries, ensuring new actors in space act responsibly, and increasing public awareness and engagement are concrete steps that can provide a broader interest in space exploration, worldwide, and build a solid basis for program sustainability. By engaging developing countries and emerging space nations in an international space exploration program, it will be possible to create a critical bottom-up support structure to support program continuity in the development and execution of future global space exploration frameworks. With a focus on stepping stones, COSPAR can support a global space exploration program that stimulates scientists in current and emerging spacefaring nations, and that will invite those in developing countries to participate—pursuing research aimed at answering outstanding questions about the origins and evolution of our solar system and life on Earth (and possibly elsewhere). COSPAR, in cooperation with national and international science foundations and space-related organizations, will advocate this stepping stone approach to enhance future cooperative space exploration efforts.  相似文献   
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