1,509 research outputs found
Telemetry coding study for the international magnetosphere explorers mother-daughter and heliocentric missions. Volume 1: Summary
The convolutional coding study on the IME Mother-Daughter and Heliocentric spacecraft is reported. The three major tasks involved in the study are summarized
Power spectrum analysis of staggered quadriphase-shift-keyed signals
Mathematical analysis of power spectrum of outputs from high-reliability communication system is used to determine system bandwidth. Analysis provides mathematical relationships of signal power spectrum at output of hard limiter for any type of baseband pulse input subjected only to output parameter constraints
Telemetry coding study for the international magnetosphere explorers, mother/daughter and heliocentric missions. Volume 2: Final report
A convolutional coding theory is given for the IME and the Heliocentric spacecraft. The amount of coding gain needed by the mission is determined. Recommendations are given for an encoder/decoder system to provide the gain along with an evaluation of the impact of the system on the space network in terms of costs and complexity
Shuttle communications design study
The design and development of a space shuttle communication system are discussed. The subjects considered include the following: (1) Ku-band satellite relay to shuttle, (2) phased arrays, (3) PN acquisition, (4) quadriplexing of direct link ranging and telemetry, (5) communications blackout on launch and reentry, (6) acquisition after blackout on reentry, (7) wideband communications interface with the Ku-Band rendezvous radar, (8) aeroflight capabilities of the space shuttle, (9) a triple multiplexing scheme equivalent to interplex, and (10) a study of staggered quadriphase for use on the space shuttle
Operations on integral lifts of K(n)
This very rough sketch is a sequel to arXiv:1808.08587; it presents evidence
that operations on lifts of the functors K(n) to cohomology theories with
values in modules over valuation rings of local number fields, indexed by
Lubin-Tate groups of such fields, are extensions of the groups of automorphisms
of the indexing group laws, by the exterior algebras on the normal bundle to
the orbits of the group laws in the space of lifts.Comment: \S 2.0 hopefully less cryptic. To appear in the proceedings of the
2015 Nagoya conference honoring T Ohkawa. Comments very welcome
The effect of molybdenum on growth rates, photosynthetic rates and nitrogen assimilation in freshwater plankton algae.
Dept. of Biological Sciences. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1973 .C28. Source: Masters Abstracts International, Volume: 40-07, page: . Thesis (M.Sc.)--University of Windsor (Canada), 1973
Univalent Foundations and the UniMath Library
We give a concise presentation of the Univalent Foundations of mathematics outlining the main ideas, followed by a discussion of the UniMath library of formalized mathematics implementing the ideas of the Univalent Foundations (section 1), and the challenges one faces in attempting to design a large-scale library of formalized mathematics (section 2). This leads us to a general discussion about the links between architecture and mathematics where a meeting of minds is revealed between architects and mathematicians (section 3). On the way our odyssey from the foundations to the "horizon" of mathematics will lead us to meet the mathematicians David Hilbert and Nicolas Bourbaki as well as the architect Christopher Alexander
Uniform generation in trace monoids
We consider the problem of random uniform generation of traces (the elements
of a free partially commutative monoid) in light of the uniform measure on the
boundary at infinity of the associated monoid. We obtain a product
decomposition of the uniform measure at infinity if the trace monoid has
several irreducible components-a case where other notions such as Parry
measures, are not defined. Random generation algorithms are then examined.Comment: Full version of the paper in MFCS 2015 with the same titl
'Building Relationships between Cities and Towns in China: The Emerging City System in Chongqing'
Among the many challenges of working on cities in China are changing urban definitions, streams of policies and plans, and even the creation of hundreds of new cities. The Chinese government has periodically changed the definition of urban places, based on population size and the built-up area, and aligned administrative divisions with cities, establishing new cities at the province, prefecture, and county levels of government. In 2014 the Chinese government released an unprecedented national urbanization plan, called the New-type Urbanization Plan (2014-2020). After three decades of rapid uneven development, this plan articulates a path to urbanization that promotes sustainable ‘people-oriented development’. All of these issues come together in the case of Chongqing, a former prefecture-level city in Sichuan province.
The government re-established Chongqing as a separate territory and new city’ at the province level in 1997, merging into the prefecture-level city that was Chongqing two other prefecture-level cities, Fuliang and Wanxian, and one prefecture, Qianjiang, creating an area comprised of multiple urban areas and a mountainous territory of rural and semi-rural counties. Figure 1. Chongqing is therefore similar to New York, New York, existing as both a city and the equivalent of a state in the U.S. system. The first international reports heralded Chongqing as ‘the largest city in the world’ because the population of the Chongqing administrative division is more than 30 million. However, with a land area (82,300 km2) twice the size of Switzerland (41,285 km2), it is not a city in any conventional sense. The government established Chongqing as an administrative city-region in relation to two large-scale developments: the reservoir area behind the Three Gorges Dam, and the ‘Open the West’ strategy (Hong, 2004). In this developmental context, Chongqing lies at the heart of a new urban system with medium and small cities governing multiple towns that anchor the urban hierarchy. This administrative complexity raises numerous questions about how meeting China’s plans for people-oriented development
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