12,097 research outputs found
Experimental study of sound and vibration transmission to a shroud-enclosed spacecraft Annual report, 20 Jan. 1967 - 20 Jan. 1968
Acoustic and mechanical vibration transmission paths to shroud enclosed spacecraf
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Human Activity Modelling in the Specification of Operational Requirements: Work in Progress
This paper describes our experience of integrating HCI concepts and techniques into a concurrent requirements engineering process called RESCUE. We focus on the use of a model of current human activity to inform specification of a future system. We show how human activity descriptions, written using a specially designed template, can facilitate the authoring of use case descriptions to be used in the elicitation of requirements for complex socio-technical systems. We describe our experience of using descriptions of human activity, written using the template, to support specification of operational requirements for DMAN, a system to support air traffic controllers in managing the departure of aircraft from airports. We end with a discussion of lessons learnt from our experience and present some ideas for future development of work in this area
SNAP-8 post shutdown gamma radiation approximations
Detector responses were calculated for normalized sources in the Perkins and King energy group structure for a SNAP 8 power system on a NASA space station. Gamma decay rates were then calculated by using an expanded, updated list of isotopic decay data, and from these, actual detector responses were found for the SNAP 8 system. The results indicate that energy-dependent calculations must be made to determine decay gamma dose rates for actual reactor configurations. A simplified method for making these calculations has been devised
The genus Distephanus (Asteraceae: Vernonieae) in southern Africa
AbstractThe southern African species of Distephanus Cass. (Asteraceae: Vernonieae) are revised. Full descriptions, illustrations, distribution maps and a key are provided for the five species recognised in the region
Dmitri Shalin Interview with Peter Manning about Erving Goffman entitled Manning-Shalin on Goffman
Interview between Dmitri Shaolin and Peter Mannin
Sustainable business investment to advance livestock health and productivity in Sub-Saharan Africa: the African Livestock Productivity & Health Advancement (A.L.P.H.A.) initiative
Livestock are an essential asset to rural communities, and the health of livestock is critical for achieving food security in regions where there is exceptionally high incidence of livestock and human disease. Sub-Saharan Africa (SSA) has amongst the highest human population growth rates in the world, with five-fold growth in Tanzania projected by 2100. Livestock productivity therefore must be improved by overcoming existing constraints to the livestock health sector, including: lack of access to quality veterinary medicines and products, poor rural extension services, limited sustainability of diagnostics services, and low education regarding animal health. Zoetis, the global animal health leader, partnered with the Bill & Melinda Gates Foundation through a $14.4M business development grant with a key focus on sustainable improvement of livestock production in SSA. In the focal countries of Nigeria, Uganda, and now Tanzania and Ethiopia, the African Livestock Health and Productivity Advancement (A.L.P.H.A.) initiative centres around three central pillars namely; Veterinary Medicines & Services, Training & Education, and Veterinary Laboratory networks. Empowerment of the veterinary profession is a key component of our aim to demonstrate the value of animal health to farmers, particularly through encouraging business acumen and highlighting the importance of correct and responsible use of veterinary medicines. After successful launch activities in Nigeria and Uganda, we seek to continue our approach in Tanzania to focus on partnerships with important distributors, veterinary laboratories, and other key contributors to the supply chain to work towards common goals engineered for future growth and longevity.
Keywords: Productivity, Sub-Saharan Africa, livestock, sustainability, diagnostic
Superintegrability on the two-dimensional hyperboloid
In this work we examine the basis functions for classical and quantum mechanical systems on the two-dimensional hyperboloid that admit separation of variables in at least two coordinate systems. We present all of these cases from a unified point of view. In particular, all of the special functions that arise via variable separation have their essential features expressed in terms of their zeros. The principal new results are the details of the polynomial bases for each of the nonsubgroup bases, not just the subgroup spherical coordinate cases, and the details of the structure of the quadratic symmetry algebras
Bounds on the diameter of Cayley graphs of the symmetric group
In this paper we are concerned with the conjecture that, for any set of
generators S of the symmetric group of degree n, the word length in terms of S
of every permutation is bounded above by a polynomial of n. We prove this
conjecture for sets of generators containing a permutation fixing at least 37%
of the points.Comment: 17 pages, 6 table
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Informing the specification of a large-scale socio-technical system with models of human activity
In this paper, we present our experience of using rich and detailed models of human activity in an existing socio-technical system in the domain of air traffic control to inform a use case-based specification of an enhanced future system, called DMAN. This work was carried out as part of a real project for Eurocontrol, the European Organisation for the Safety of Air Navigation. We describe, in outline, the kinds of models we used, and present some examples of the ways in which these models influenced the specification of use cases and requirements for the future system. We end with a discussion of lessons learnt
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