Relative Velocity as a Metric for Probability of Collision Calculations

Collision risk assessment metrics, such as the probability of collision calculation, are based largely on assumptions about the interaction of two objects during their close approach. Specifically, the approach to probabilistic risk assessment can be performed more easily if the relative trajectories of the two close approach objects are assumed to be linear during the encounter. It is shown in this analysis that one factor in determining linearity is the relative velocity of the two encountering bodies, in that the assumption of linearity breaks down at low relative approach velocities. The first part of this analysis is the determination of the relative velocity threshold below which the assumption of linearity becomes invalid. The second part is a statistical study of conjunction interactions between representative asset spacecraft and the associated debris field environment to determine the likelihood of encountering a low relative velocity close approach. This analysis is performed for both the LEO and GEO orbit regimes. Both parts comment on the resulting effects to collision risk assessment operations

Arrow 227: Air transport system design simulation

The Arrow 227 is a student-designed commercial transport for use in a overnight package delivery network. The major goal of the concept was to provide the delivery service with the greatest potential return on investment. The design objectives of the Arrow 227 were based on three parameters; production cost, payload weight, and aerodynamic efficiency. Low production cost helps to reduce initial investment. Increased payload weight allows for a decrease in flight cycles and, therefore, less fuel consumption than an aircraft carrying less payload weight and requiring more flight cycles. In addition, fewer flight cycles will allow a fleet to last longer. Finally, increased aerodynamic efficiency in the form of high L/D will decrease fuel consumption

When I Send You A Picture Of Berlin : You\u27ll Know It\u27s Over, Over There, I\u27m Coming Home

https://digitalcommons.library.umaine.edu/mmb-vp/2678/thumbnail.jp

Leveraging the Success of the CubeSat Standard to Create a SmallSat Standard for ESPA Spacecraft

The space industry has found significant utility in short turn-around, small satellite missions. There has also been a significant increase in both rideshare and dedicated launch opportunities for small satellites around the world. Small satellites can be developed in much shorter timelines than the traditional, large spacecraft missions. In order to fully leverage the short-development time of small satellites, a standardized design approach is required. Following the success of the CubeSat Design Specification (CDS), it is clear that a standard set of specifications in a concise document allows developers to design their spacecraft without knowledge of their specific launch opportunity. A publicly available standard provides developers and launch vehicles with a set of common parameters for initial design and analyses. CubeSats have shown that a standardization approach is effective at getting missions to space quickly and inexpensively. As the small satellite industry continues to flourish, adapting to the new paradigm is crucial to widespread success

Prospectus, May 6, 1976

REID ELECTED STU-GO PRESIDENT; Three victories: Reagan upsets Ford; Graduation May 21; Student art show; PC news in brief; Editorial: Where is display case?; Letters to the Editor: \u27Children should not be underestimated\u27; Tuition increase protest set for May 12; 58 cases in Champaign: Incidence of child abuse increasing; Return to Wilder\u27s \u27Town\u27; 1st Mother\u27s Day - 1908; Extended LRC hours; Parkland Candidates for graduation - 1976; Steps for completion of fall registration; ISU scholarships - Fairfield; PBC offers $25,000; Images on sale Monday; Summer Session: Classes start June 7; See ya\u27all next fall: Parting glances; Williams wins award; Country Bouquet: Cowboy; Counseling searches for student aides; Community band to present bicentennial concert; Little Theater opens Musical season; Final Examination Schedule - Spring Semester, 1975-76; CIA at PC; Notice; Classifieds; Summer basketball camp; Henderson IPRS head; Westjohn named to Olympic team; Oliver to Baylor; Illini Gym Club at P/C; Wind Down IMhttps://spark.parkland.edu/prospectus_1976/1016/thumbnail.jp

Influence of Urban Landscapes on Population Dynamics in a Short-Distance Migrant Mosquito: Evidence for the Dengue Vector Aedes aegypti

Worldwide, 2.5 billion people are at risk for dengue infection, with no vaccine or treatment available. Thus dengue prevention is largely focused on controlling its mosquito vector, Aedes aegypti. Traditional mosquito control approaches typically include insecticide applications and breeding site source reduction. Presently, novel dengue control measures including the sterile insect technique and population replacement with dengue-incompetent transgenic mosquitoes are also being considered. Success of all population control programs is in part dependent upon understanding mosquito population ecology, including how anthropogenic effects on the urban landscape influence dispersal and expansion. We conducted a two year population genetic study examining how a major metropolitan highway impacts mosquito dispersal in Trinidad, West Indies. As evidenced by significant differentiation using both nuclear and mitochondrial DNA sequences, the highway acted as a significant barrier to dispersal. Our results suggest that anthropogenic landscape features can be used effectively to enhance population suppression/replacement measures by defining mosquito control zones along recognized landscape barriers that limit population dispersal

Trends in testing: highlights of a global survey

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Renewable Energy Incentive Rates: Potential Opportunities for Iowa Farmers

Renewable energy is already generating significant benefits to Iowa‘s economy and environment. Thousands of Iowans are employed at companies that provide goods and services for wind energy and solar energy. Meanwhile, the thousands of recently installed wind turbines have allowed Iowa utilities to generate less electricity from fossil - fueled power plants, which means cleaner air and water for Iowa and beyond. Compared to just ten years ago, there has been a huge increase in the renewable energy technologies installed in both urban and rural Iowa, but the state has only begun to tap the enormous potential for renewable energy. As these resources are developed with solar photovoltaic panels, solar hot water systems, wind turbines, and other technologies, the considerable economic and environ mental benefits will only grow

Shining new light on mammalian diving physiology using wearable near-infrared spectroscopy

Investigation of marine mammal dive-by-dive blood distribution and oxygenation has been limited by a lack of non-invasive technology for use in freely diving animals. Here, we developed a non-invasive near-infrared spectroscopy (NIRS) device to measure relative changes in blood volume and haemoglobin oxygenation continuously in the blubber and brain of voluntarily diving harbour seals. Our results show that seals routinely exhibit preparatory peripheral vasoconstriction accompanied by increased cerebral blood volume approximately 15 s before submersion. These anticipatory adjustments confirm that blood redistribution in seals is under some degree of cognitive control that precedes the mammalian dive response. Seals also routinely increase cerebral oxygenation at a consistent time during each dive, despite a lack of access to ambient air. We suggest that this frequent and reproducible reoxygenation pattern, without access to ambient air, is underpinned by previously unrecognised changes in cerebral drainage. The ability to track blood volume and oxygenation in different tissues using NIRS will facilitate a more accurate understanding of physiological plasticity in diving animals in an increasingly disturbed and exploited environment