Affine Toda Solitons and Automorphisms of Dynkin Diagrams

Using Hirota's method, solitons are constructed for affine Toda field theories based on the simply-laced affine algebras. By considering automorphisms of the simply-laced Dynkin diagrams, solutions to the remaining algebras, twisted as well as untwisted, are deduced.Comment: 21 page

On the topological charges of the affine toda solitons

This thesis investigates the two dimensional, integrable field theories known as the affine Toda field theories, which are based on the Kac-Moody algebras with zero central extension. In particular, the construction of static solitons in these theories and their topological charges are considered. Following a general overview of the affine Toda theories and the Kac-Moody structure which underlies them, the construction of solitons in the a(_n)((^1)) theory using Hirota's method, originally used by HoUowood, is generalized and extended to the remaining theories. The soliton masses are calculated and general expressions presented for the twisted as well as the untwisted theories. The major results of this work concern the calculation of topological charge, one of the infinite number of conserved quantities that each theory possesses. Firstly, the a(_n)((^1)) model is considered. An expression for the number of charges associated with each soliton, as well as a general expression for the charges themselves, is constructed. The previously alluded to connection between the charges and the associated fundamental representations is proven showing that the charges are, in general, a subset of the weights lying in these representations. For the a(_n)((^1)) theory, the charges associated with each soliton can be derived from just one by making use of the cyclic symmetry of the model's extended Dynkin diagram. Further, the action of this symmetry on the set of charges is synonymous with the action of a Coxeter element. It is found that the ordering of the Weyl reflections which make up this element is important (except when the end-point solitons are considered) - the familiar "black-white" ordering doesn't work. The multisolitons of the theory are considered and it is shown that when the individual solitons are sufficiently well separated their topological charges simply add together. Multi-solitons can be constructed having topological charge equal to each of the simple roots, and can therefore be used to construct further solitons filling the entire weight lattice. Next, the topological charges of the remaining aflttne Toda theories are investigated. For the infinite series of algebras the number of topological charges and expressions for the charges themselves are derived. For the remaining cases, the charges are calculated explicitly. This thesis concludes with some comments on more recent work into the theory of quantum solitons and considers further lines of enquiry

Unit organization of the topic Exponents and radicals in intermediate algebra

Thesis (M.A.)--Boston University, 1948. This item was digitized by the Internet Archive

<i>Rehabilitation doxa</i> and practitioner judgment. An analysis of symbolic violence on health care provision in the Scottish prison system

This paper presents an analysis of the symbolic conditions which govern health care provision in the Scottish prison system. The paper considers the wider context of Scottish prisons, where health care provision follows a similar structure both in juvenile and adult prisons. Our intention is to provoke a debate about the doxa (Bourdieu, 1977), which underlies decision making in respect of health care in prison, in a political environment where pragmatism, allied to the ‘pathologisation’ of social policies, health and criminal justice has been a hegemonic force.<br/

Development of Semi-Span Model Test Techniques

A computational investigation was performed to support the development of a semispan model test capability in the NASA Langley Research Center's National Transonic Facility. This capability is desirable for the testing of advanced subsonic transport aircraft at full-scale Reynolds numbers. A state-of-the-art three-dimensional Navier-Stokes solver was used to examine methods to improve the flow over a semi-span configuration. First, a parametric study is conducted to examine the influence of the stand-off height on the flow over the semispan model. It is found that decreasing the stand-off height, below the maximum fuselage radius, improves the aerodynamic characteristics of the semi-span model. Next, active sidewall boundary layer control techniques are examined. Juncture region blowing jets, upstream tangential blowing, and sidewall suction are found to improve the flow over the aft portion of the semispan model. Both upstream blowing and suction are found to reduce the sidewall boundary layer separation. The resulting near surface streamline patterns are improved, and found to be quite similar to the full-span results. Both techniques however adversely affect the pitching moment coefficient

Wind tunnel results of the high-speed NLF(1)-0213 airfoil

Wind tunnel tests were conducted to evaluate a natural laminar flow airfoil designed for the high speed jet aircraft in general aviation. The airfoil, designated as the High Speed Natural Laminar Flow (HSNLF)(1)-0213, was tested in two dimensional wind tunnels to investigate the performance of the basic airfoil shape. A three dimensional wing designed with this airfoil and a high lift flap system is also being evaluated with a full size, half span model

Evaluation of microwave characterization methods for additively manufactured materials

Additive manufacturing (AM) has become more important and common in recent years. Advantages of AM include the ability to rapidly design and fabricate samples much faster than traditional manufacturing processes and to create complex internal geometries. Materials are crucial components of microwave systems and proper and accurate measurement of their dielectric properties is important to aid a high level of accuracy in design. There are numerous measurement techniques and finding the most appropriate method is important and requires consideration of all different factors and limitations. One limitation of sample preparation is that the sample size needs to fit in the measurement method. By utilizing the advantage of additive manufacturing, the material can be characterized using different measurement methods. In this paper, the additive manufacturing process and dielectric measurement methods have been critically reviewed. The test specimens for measuring dielectric properties were fabricated using fused filament fabrication (FFF)-based additive manufacturing and were measured using four different commercial dielectric properties measurement instruments including split post dielectric resonator (SPDR), rectangular waveguide, TE01δ cavity resonator, and open resonator. The measured results from the four techniques have been compared and have shown reasonable agreement with measurements within a 10 percent range

Functional diversity of marine ecosystems after the Late Permian mass extinction event

Article can be accessed from http://www.nature.com/ngeo/journal/v7/n3/full/ngeo2079.htmlThe Late Permian mass extinction event was the most severe such crisis of the past 500 million years and occurred during an episode of global warming. It is assumed to have had significant ecological impact, but its effects on marine ecosystem functioning are unknown and the patterns of marine recovery are debated. We analysed the fossil occurrences of all known Permian-Triassic benthic marine genera and assigned each to a functional group based on their inferred life habit. We show that despite the selective extinction of 62-74% of marine genera there was no significant loss of functional diversity at the global scale, and only one novel mode of life originated in the extinction aftermath. Early Triassic marine ecosystems were not as ecologically depauperate as widely assumed, which explains the absence of a Cambrian-style Triassic radiation in higher taxa. Functional diversity was, however, significantly reduced in particular regions and habitats, such as tropical reefs, and at these scales recovery varied spatially and temporally, probably driven by migration of surviving groups. Marine ecosystems did not return to their pre-extinction state, however, and radiation of previously subordinate groups such as motile, epifaunal grazers led to greater functional evenness by the Middle Triassic

A Quality Assessment of a Collaborative Model of a Pediatric Antimicrobial Stewardship Program

BACKGROUND: Infectious Diseases Society of America guidelines recommend that key antimicrobial stewardship program (ASP) personnel include an infectious disease (ID) physician leader and dedicated ID-trained clinical pharmacist. Limited resources prompted development of an alternative model by using ID physicians and service-based clinical pharmacists at a pediatric hospital. The aim of this study was to analyze the effectiveness and impact of this alternative ASP model. METHODS: The collaborative ASP model incorporated key strategies of education, antimicrobial restriction, day 3 audits, and practice guidelines. High-use and/or high-cost antimicrobial agents were chosen with audits targeting vancomycin, caspofungin, and meropenem. The electronic medical record was used to identify patients requiring day 3 audits and to communicate ASP recommendations. Segmented regression analyses were used to analyze quarterly antimicrobial agent prescription data for the institution and selected services over time. RESULTS: Initiation of ASP and day 3 auditing was associated with blunting of a preexisting increasing trend for caspofungin drug starts and use and a significant downward trend for vancomycin drug starts (relative change -12%) and use (-25%), with the largest reduction in critical care areas. Although meropenem use was already low due to preexisting requirements for preauthorization, a decline in drug use (-31%, P = .021) and a nonsignificant decline in drug starts (-21%, P = .067) were noted. A 3-month review of acceptance of ASP recommendations found rates of 90%, 93%, and 100% for vancomycin, caspofungin, and meropenem, respectively. CONCLUSIONS: This nontraditional ASP model significantly reduced targeted drug usage demonstrating acceptance of integration of service-based clinical pharmacists and ID consultants