389 research outputs found
Emergent Form from Structural Optimisation of the Voronoi Polyhedra Structure
In the course of the exploration of computational means in the architectural design process, in order to investigate more complex, adaptive geometries, the Voronoi diagram has recently gained some attention, being a three-dimensional space-filling structure which is modular but not repetitive. The project looks at the Voronoi diagram as a load-bearing structure, and whether it can be useful for structural optimisation. Hereby the edges of the Voronoi polyhedra are regarded as structural members of a statical system, which then is assessed by structural analysis software. Results seem to indicate that the Voronoi approach produces a very specific structural as well as spatial type of order. Through the dislocation of the Voronoi cells, the statical structure becomes more complex through emergent topology changes, and the initially simple spatial system becomes much more complex through emerging adjacencies and interconnections between spaces. The characteristics of the emerging form, however, lie rather in the complexity how shifted spaces and parts are fitted together, than in a radical overall emergent geometry. Spatially as well as a structurally, the form moves from a simple modular repetitive system towards a more complex adaptive one, with interconnected parts which cannot stand alone but rather form an organic whole
Urban identity through quantifiable spatial attributes: coherence and dispersion of local identity through the automated comparative analysis of building block plans
This analysis investigates whether and to what degree quantifiable spatial attrib-utes, as expressed in plan representations, can capture elements related to the ex-perience of spatial identity. By combining different methods of shape and spatial analysis it attempts to quantify spatial attributes, predominantly derived from plans, in order to illustrate patterns of interrelations between spaces through an ob-jective automated process. The study focuses on the scale of the urban block as the basic modular unit for the formation of urban configurations and the issue of spa-tial identity is perceived through consistency and differentiation within and amongst urban neighbourhoods
Governance of the world food system and crisis prevention
The present study offers a framework, rooted in Disaster Studies. The next few sections will first discuss the analytical tool box, which we have largely drawn from Disaster Studies. Thereafter the food regime will be looked into in the quantitative (food security, Section 3.1) and qualitative sense (food safety, Section 3.2), and the actors and rules and regulations for international food aid discussed. It will become clear that the private sector has a key role to play in both categories. Chapter 4 calls attention to the increasing complexities and uncertainties in the global food system that complicate food governance. To get anything done at all, a simplification seems necessary, such as declaring a food problem a safety issue
Weyl multiplets of N=2 conformal supergravity in five Dimensions
We construct the Weyl multiplets of N=2 conformal supergravity in five
dimensions. We show that there exist two different versions of the Weyl
multiplet, which contain the same gauge fields but differ in the matter field
content: the Standard Weyl multiplet and the Dilaton Weyl multiplet. At the
linearized level we obtain the transformation rules for the Dilaton Weyl
multiplet by coupling it to the multiplet of currents corresponding to an
on-shell vector multiplet. We construct the full non-linear transformation
rules for both multiplets by gauging the D=5 superconformal algebra F^2(4). We
show that the Dilaton Weyl multiplet can also be obtained by solving the
equations of motion for an improved vector multiplet coupled to the Standard
Weyl multiplet.Comment: 40 pages, v2: note added and minor corrections; v3: corrections in
(3.19-23); v4: + sign added in (3.19
Embedding Branes in Flat Two-time Spaces
We show how non-near horizon, non-dilatonic -brane theories can be
obtained from two embedding constraints in a flat higher dimensional space with
2 time directions. In particular this includes the construction of D3 branes
from a flat 12-dimensional action, and M2 and M5 branes from 13 dimensions. The
worldvolume actions are found in terms of fields defined in the embedding
space, with the constraints enforced by Lagrange multipliers.Comment: LaTex, 8 pages. Contribution to the TMR Conference on Quantum aspects
of gauge theories, supersymmetry and unification. Paris, 1-7 September 199
Are white matter lesions directly associated with cognitive impairment in patients with lacunar infarcts?
Forty-four patients (mean age 66, SD 8 years) with either clinical evidence of a focal lacunar syndrome (n = 36) or with disorders of memory or gait (n = 8) in the presence of a lacunar infarct on CT were studied for cognitive functioning and for the presence of white matter lesions on MRI. MR images were assessed by a neurologist and a neuroradiologist blinded to the clinical data. Thirty-six patients had one or more lacunar infarcts on CT or MRI (in the thalamus in 5, in the caudate nucleus in 3 and in the internal capsule or corona radiata in the remaining patients). Twelve patients had multiple infarcts. Severe lesions of the white matted were found in 13 patients, mild to moderate lesions in 20 patients. Scores on Digit Span, Digit Symbol and delayed recall of the 15-Words test were significantly lower in the group with severe lesions, whilst there was a trend in the same direction for the Cognitive part of the Cambridge Examination of Mental Disorders in the Elderly, the Trailmaking B, Stroop colour interference test and the delayed visual reproduction of the Wechsler Memory Scale. These findings suggest that diffuse lesions of the white matter are an independent factor in the pathogenesis of intellectual dysfunction, also in patients with lacunar infarcts, but a truly independent analysis is difficult because the most severe involvement of the white matter tended to be associated with the largest number of lacunar infarcts
Isometric Embedding of BPS Branes in Flat Spaces with Two Times
We show how non-near horizon p-brane theories can be obtained from two
embedding constraints in a flat higher dimensional space with 2 time
directions. In particular this includes the construction of D3 branes from a
flat 12-dimensional action, and M2 and M5 branes from 13 dimensions. The
worldvolume actions are determined by constant forms in the higher dimension,
reduced to the usual expressions by Lagrange multipliers. The formulation
affords insight in the global aspects of the spacetime geometries and makes
contact with recent work on two-time physics.Comment: 29 pages, 10 figures, Latex using epsf.sty and here.sty; v2:
reference added and some small correction
Student Recital: Clifford Derix, Baritone
Kemp Recital Hall Saturday Evening November 19, 1994 6:00 p.m
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