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Driving in the wrong lane: towards a longer life-span of cars
Within the context of product longevity, one especially impactful and ubiquitous product demands further research: the car. Car longevity has been addressed in the context of product life extension and product lifetime optimisation but there have been a few studies on car longevity in the context of business and none specifically from an industrial design context. This paper presents initial findings from preliminary interviews with key industry representatives such as car designers and engineers. It discusses the barriers to and opportunities for designing a car with a longer life-span. This and further data will later be analysed in order to produce a design framework to inform car
designers on life-span and usage optimization through design. Strategies such as increased longevity or use-intensity can potentially reduce the throughput - and thereafter the consumption - of cars. Such a shift in the automotive sector would support the transition from a linear economy to a more sustainable one. The initial findings, however, suggest that a longer life car is not an uncompromised solution and important concessions would have to be made in order to make this an acceptable
product
Effect of the spin-orbit interaction and the electron phonon coupling on the electronic state in a silicon vacancy
The electronic state around a single vacancy in silicon crystal is
investigated by using the Green's function approach. The triply degenerate
charge states are found to be widely extended and account for extremely large
elastic softening at low temperature as observed in recent ultrasonic
experiments. When we include the LS coupling on each Si
atom, the 6-fold spin-orbital degeneracy for the state with the valence
+1 and spin 1/2 splits into doublet groundstates and
quartet excited states with a reduced excited energy of . We also consider the effect of couplings between electrons and
Jahn-Teller phonons in the dangling bonds within the second order perturbation
and find that the groundstate becomes quartet which is responsible
for the magnetic-field suppression of the softening in B-doped silicon.Comment: 4 pages, 2 figure
Interior decoration. 1. Scope and affinity with architecture
AN instinctive urge for decoration has been felt by human beings since earliest times, when man first scratched crude designs on the walls of his cave, or daubed his primitive dwelling with muds, pigments and anything else at his disposal
Late time cosmological phase transitions 1: Particle physics models and cosmic evolution
We described a natural particle physics basis for late-time phase transitions in the universe. Such a transition can seed the formation of large-scale structure while leaving a minimal imprint upon the microwave background anisotropy. The key ingredient is an ultra-light pseudo-Nambu-Goldstone boson with an astronomically large (O(kpc-Mpc)) Compton wavelength. We analyze the cosmological signatures of and constraints upon a wide class of scenarios which do not involve domain walls. In addition to seeding structure, coherent ultra-light bosons may also provide unclustered dark matter in a spatially flat universe, omega sub phi approx. = 1
Metastable Cosmic Strings in Realistic Models
We investigate the stability of the electroweak Z-string at high
temperatures. Our results show that while finite temperature corrections can
improve the stability of the Z-string, their effect is not strong enough to
stabilize the Z-string in the standard electroweak model. Consequently, the
Z-string will be unstable even under the conditions present during the
electroweak phase transition. We then consider phenomenologically viable models
based on the gauge group and show
that metastable strings exist and are stable to small perturbations for a large
region of the parameter space for these models. We also show that these strings
are superconducting with bosonic charge carriers. The string superconductivity
may be able to stabilize segments and loops against dynamical contraction.
Possible implications of these strings for cosmology are discussed.Comment: 24 pages, 2 figures (available on request); HUTP-92/A032,
Fermilab-Pub-92/228-
The Anglo-American Reception of Carl Schmitt from the 1930s to the Early 2000s
This thesis examines the Anglo-American reception, from the 1930s to the early 2000s, of the ideas of the German political theorist Carl Schmitt. The introduction provides an overview the key concepts in Schmitt’s writings in the 1920s. Chapter one examines Schmitt’s influence on the German-Jewish émigré political theorists Leo Strauss and Hans Morgenthau, in an attempt to explain how Schmitt’s ideas were initially transported from Germany to the U.S. The second chapter is a more detailed case study of the American leftist journal, Telos, which played a key role in introducing Schmitt’s writings to a broader, English language audience in the late 1980s and 1990s. Chapter three examines the reception of Schmitt among left and left-liberal Anglo-American political theorists more generally. Both chapter two and three address the larger question of which elements of the Anglo-American left were drawn to Schmitt and why the ideas of this conservative German thinker – and former Nazi – still seemed relevant to them
Improving the Analyst and Decision-Maker’s Perspective through Uncertainty Visualization
This thesis constructs the Taxonomy of Uncertainty and an approach for enhancing the information in decision support systems. The hierarchical categorization of numerous causes for uncertainty defines the taxonomy, which fostered the development of a technique for visualizing uncertainty. This technique is fundamental to expressing the multi-dimensional uncertainty that can be associated with any object. By including and intuitively expressing uncertainty, the approach facilitates and enhances intuition and decision-making without undue information overload. The resulting approach for enhancing the information involves recording uncertainty, identifying the relevant items, computing and visualizing uncertainty, and providing interaction with the selection of uncertainty. A prototype embodying this approach to enhancing information by including uncertainty was used to validate these efforts. Evaluation responses of a small sample space support the thesis that the decision-maker\u27s knowledge is enhanced with enlightening information afforded by including and visualizing uncertainty, which can improve the decision-making process. Although the concept was initially conceived to help decision support system users deal with uncertainty, this methodology and these ideas can be applied to any problem where objects with many potential reasons for uncertainty are the focus of the decision-making
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