6,807 research outputs found
A geometric basis for the standard-model gauge group
A geometric approach to the standard model in terms of the Clifford algebra
Cl_7 is advanced. A key feature of the model is its use of an algebraic spinor
for one generation of leptons and quarks. Spinor transformations separate into
left-sided ("exterior") and right-sided ("interior") types. By definition,
Poincare transformations are exterior ones. We consider all rotations in the
seven-dimensional space that (1) conserve the spacetime components of the
particle and antiparticle currents and (2) do not couple the right-chiral
neutrino. These rotations comprise additional exterior transformations that
commute with the Poincare group and form the group SU(2)_L, interior ones that
constitute SU(3)_C, and a unique group of coupled double-sided rotations with
U(1)_Y symmetry. The spinor mediates a physical coupling of Poincare and
isotopic symmetries within the restrictions of the Coleman--Mandula theorem.
The four extra spacelike dimensions in the model form a basis for the Higgs
isodoublet field, whose symmetry requires the chirality of SU(2). The charge
assignments of both the fundamental fermions and the Higgs boson are produced
exactly.Comment: 17 pages, LaTeX requires iopart. Accepted for publication in J. Phys.
A: Math. Gen. 9 Mar 2001. Typos correcte
Enhancing teaching skills and fostering critical reflective practices in the professional development of university teachers.
Over the last two decades or so, important new initiatives have been introduced into undergraduate education to advance learning. These initiatives bear witness to the fact that there are higher education professionals who are intimately interested in the transformation of approaches to teaching and learning in the academy (Chisholm, 2007; Costa & Kallick, 1993; O‘Banion, 1997; Wingspread Group on Higher Education, 1993). Some are also interested in thoroughgoing transformation of the teaching and learning through faculty development initiatives. Many of these innovative practices hold out great promise for real advances in student learning and even for changing the culture of higher education (Barr & Tagg, 1995; Smith, 2004). In this regard, reflective teaching and learning is important in professional development and for better teaching practices. The use of critical friends can also assist the processes of reflecting on teaching and learning from teaching and the overall advancement of teaching in higher education
Perspectives of Faculty on Student Evaluations of Teaching at an Anglophone Caribbean University
Student evaluations of teaching (SET) remain the most prominent and the primary source of data used to evaluate classroom teaching at many colleges and universities internationally (Cashin, 1999; Felten, Little & Pingree, 2004; Spooren, Brockx & Mortelmans, 2013; Zabaleta, 2007). This is also the case in the Anglophone Caribbean and at the leading research institution in the Anglophone Caribbean; the University of the West Indies, student evaluations of teaching remain the only method of the evaluation of the teaching of the faculty. Generally, from time to time, these evaluations are experienced as intrusive, invasive, frustrating and frightening (Ory, 2001). There are instances where faculty members become defensive and extremely protective of themselves and their pedagogy when poor evaluation results are communicated to them. Fink (2008) has asserted that the widespread use of SET is not driving instructional improvement; instead it is creating widespread cynicism about teaching evaluations
Let Them be Free: Adult Education in an Underground LGBT Church in Jamaica
This study investigated the experiences of members of an underground LGBT church in Jamaica and their educational practices. In particular, to understand how they negotiated and navigated their identity in light of their spirituality and religious commitments in the context of a culture that was hostile to the LGBT community
Counter-hegemonic pedagogy: Activism and the life of the organic intellectual
The continuing search for counter-hegemonic pedagogy is underscored. Aspects of the search are brought into the conversation and useful approaches for advancing emancipatory pedagogy are offered and discussed
Study of controlled diffusion stator blading. 1. Aerodynamic and mechanical design report
Pratt & Whitney Aircraft is conducting a test program for NASA in order to demonstrate that a controlled-diffusion stator provides low losses at high loadings and Mach numbers. The technology has shown great promise in wind tunnel tests. Details of the design of the controlled diffusion stator vanes and the multiple-circular-arc rotor blades are presented. The stage, including stator and rotor, was designed to be suitable for the first-stage of an advanced multistage, high-pressure compressor
Fabrication and application of short and novel structure in-fibre Bragg gratings
This thesis presents details on progress made in the fabrication and application of short and novel structure fibre Bragg gratings. The basic theoretical concepts of in-fibre Bragg gratings and photosensitive mechanisms are introduced together with an overview of fabrication methods and applications presented to date. The fabrication of fibre Bragg gratings using a quadrupled Nd:YAG laser is presented and some of the issues of grating fabrication using a fabrication using a phasemask are investigated, including the variation of the separation of the fibre and phasemask, and other alignment issues. A new apodisation technique is presented, enabling the production of gratings with a wide range of spectral profiles. The technique is used to investigate the design and fabrication of length limited fibre Bragg gratings for use in telecommunication systems as filters. Application to devices designed for use in WDM systems is presented. The use of fibre Bragg gratings as high spatial resolution distributed sensors is investigated. Grating sensing arrays comprising very short apodised gratings are demonstrated and Chirped Moiré gratings are implemented as distributed sensors achieving high spatial resolution with miniature point sensing sub-elements. A novel grating sensing element designed to imitate an interferometer is also presented. Finally, the behaviour of gratings fabricated in Boron-Germania-co-doped fibre is investigated, revealing atypical behaviour of the Bragg wavelength during ageing
It’s Slippery Out There’: Outsider\u27s Perspectives of the Navigational Skills of African American Undergraduates in a Predominantly White Midwestern University
In this qualitative research study conducted at a predominantly white institution in the Midwest USA, thirteen successful African American college students were interviewed about their in-class and out-of-class experiences at the institution. The research focus was how they were experiencing college and how they were navigating the higher education terrain. The results provided evidence of an exclusionary curriculum, racial and microagressions, verbal abuse, problematic psychosocial environment and yet the defying of the odds to survive and thrive
On the Change in Archivability of Websites Over Time
As web technologies evolve, web archivists work to keep up so that our
digital history is preserved. Recent advances in web technologies have
introduced client-side executed scripts that load data without a referential
identifier or that require user interaction (e.g., content loading when the
page has scrolled). These advances have made automating methods for capturing
web pages more difficult. Because of the evolving schemes of publishing web
pages along with the progressive capability of web preservation tools, the
archivability of pages on the web has varied over time. In this paper we show
that the archivability of a web page can be deduced from the type of page being
archived, which aligns with that page's accessibility in respect to dynamic
content. We show concrete examples of when these technologies were introduced
by referencing mementos of pages that have persisted through a long evolution
of available technologies. Identifying these reasons for the inability of these
web pages to be archived in the past in respect to accessibility serves as a
guide for ensuring that content that has longevity is published using good
practice methods that make it available for preservation.Comment: 12 pages, 8 figures, Theory and Practice of Digital Libraries (TPDL)
2013, Valletta, Malt
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