Dipole-dipole dispersion interactions between neutrons

We investigate the long-range interactions between two neutrons utilizing recent data on the neutron static and dynamic electric and magnetic dipole polarizabilities. The resulting long-range potentials are used to make quantitative comparisons between the collisions of a neutron with a neutron and a neutron with a proton. We also assess the importance of the first pion production threshold and first excited state of the nucleon, the $\Delta$-resonance ($J^{\pi}$ = + 3/2, I = 3/2). We found both dynamical effects to be quite relevant for distances r between ~ 50 fm up to ~$10^3$ fm in the nn system, the neutron-wall system and in the wall-neutron-wall system, reaching the expected asymptotic limit beyond that. Relevance of our findings to the confinement of ultra cold neutrons inside bottles is discussed.Comment: 11 pages, 12 figures, Version to be published in the European Physical Journal A (2017

Low-Erosion Nozzle Materials for Long-Duration Hybrid Rocket Burns

Hybrid rocket systems, which employ a solid fuel grain and a liquid oxidizer, are a low-cost and environmentally friendly alternative to traditional rocket systems. However, hybrid rockets suffer from an increased nozzle throat erosion rate, which impacts motor performance and reliability. To address this issue several materials and low-erosion nozzle configurations were tested. The results of the testing campaign produced a nozzle that reduce the throat erosion rate five-fold

The Relative Importance of Physical Versus Service Attributes with Respect to Small Business Vendor Selection

Recent literature on the topic of vendor selection has focused on a broad, macro view of the relationship between the selection and buying processes (see e.g., Dempsey, 1978; Holt, 1981). However, most of the studies have not examined such processes in the context of the small business enterprise nor have they discriminated between the importance of physical versus service attributes. A recent study by Manzer, Ireland, and Van Auken (1981) did employ the small business in a matrix approach to vendor selection. However, there appears to be a paucity of research involving the relative importance of physical versus service attributes by small businesses in their vendor selection

Architecture, physical activity and a capability evaluative framework: satisfaction is not enough

Despite recognition that building design can contribute to human health by facilitating increased incidental physical activity, knowledge of how building design can enable this is underdeveloped. Further, there is evidence that design features introduced to support routine physical activity and improve occupant satisfaction may not necessarily lead to increases in actual physical activity. Evaluative frameworks encompassing a range of individual, organisational and built environment factors that contribute to shaping occupant behaviour may provide insight into how buildings can support greater levels of routine physical activity. This paper argues that capability theory can inform our understandings of the dynamic interrelationship between building design and building use. In this paper we describe our approach to developing a framework for capabilities-based evaluation of buildings and building occupant physical activity. Based on a capability perspective we consider the intersection of building ‘domains’ and ‘functionings’ that influence occupant physical activity; and question how such evaluations could account for a range of occupants. The research is of relevance to those engaged in the production of architectural environments and evaluation tools that support physical activity—inclusive of building designers, procurers, managers and occupants

The Importance Of Culture Change And Change Management In Successful Implementation Of Sap Enterprise Resource Planning Systems

Enterprise Resource Planning (ERP) has enabled organizations to connect vendors, the organization, and customers in an almost seamless manner with real-time accurate communication and information. In an increasingly competitive environment, businesses are looking for ways to become more competitive within their marketplace. Many are turning to ERP solutions to facilitate multiple competitive priorities to stand above competing businesses or to create a new competitive advantage. Critical success factors and change management are the primary vehicles for the achievement of success in the adoption of these systems. This research studies how change management becomes a significant link to successful ERP implementation