Using simulations and artificial life algorithms to grow elements of construction

'In nature, shape is cheaper than material', that is a common truth for most of the plants and other living organisms, even though they may not recognize that. In all living forms, shape is more or less directly linked to the influence of force, that was acting upon the organism during its growth. Trees and bones concentrate their material where thy need strength and stiffness, locating the tissue in desired places through the process of self-organization. We can study nature to find solutions to design problems. That’s where inspiration comes from, so we pick a solution already spotted somewhere in the organic world, that closely resembles our design problem, and use it in constructive way. First, examining it, disassembling, sorting out conclusions and ideas discovered, then performing an act of 'reverse engineering' and putting it all together again, in a way that suits our design needs. Very simple ideas copied from nature, produce complexity and exhibit self-organization capabilities, when applied in bigger scale and number. Computer algorithms of simulated artificial life help us to capture them, understand well and use where needed. This investigation is going to follow the question : How can we use methods seen in nature to simulate growth of construction elements? Different ways of extracting ideas from world of biology will be presented, then several techniques of simulated emergence will be demonstrated. Specific focus will be put on topics of computational modelling of natural phenomena, and differences in developmental and non-developmental techniques. Resulting 3D models will be shown and explained

On-line condition monitoring of transition assets

There are a number of medium voltage (MV) power distribution cable networks worldwide that are constructed predominantly of mass impregnated paper cables - London being one of these. Paper insulated lead covered (PILC) cables were extensively laid in the 50s and 60s before the introduction of cheaper polymeric alternatives that were sufficiently reliable. The current operational state of these networks has shown a gradual increase in failure rates of the previously reliable paper cables that are drawing to the end of their expected design life. Utilities are faced with the prospect of the impending failure of large sections of their prized asset and are keen to develop tools to better understand the health of their hardware. The analysis of partial discharge (PD) signals produced by the cables has been identified as a economically viable option to provide continuous condition monitoring of PILC cable circuits. Clearly, a comprehensive understanding of how PD activity relates to the various failure mechanisms exhibited by cable circuits in the field is required. A recently published technique for PD source discrimination was coupled with an understanding of the experiment and applied to the experiment data to isolate the signals specific to each degradation mechanism [1]. This technique has been applied to both rotation machines and transformer systems with promising results. PD signal discrimination is seen as the first step towards an autonomous condition monitoring futur

Exact spectrum for n electrons in the single band Hubbard model

The energy spectrum and the correlation functions for n electrons in the one-dimensional single band Hubbard model with periodic boundary conditions are calculated exactly. For that purpose the Hamiltonian is transformed into a set of Hamiltonians, corresponding to systems of spinless fermions.\ud Our results include the results of Mei and Chen, presented in a recent paper

Can you take the heat? – Geothermal energy in mining

In 2013, there are less than 20 documented examples of operational geothermal systems on mine sites worldwide. This is surprising, since on remote mine sites, where fuels may have to be shipped in over great distances, heating and cooling from low-enthalpy geothermal sources may have a significant advantage in operational cost over conventional energy sources. A review of factors affecting the feasibility of geothermal systems on mining projects has been undertaken, and has identified the possible configurations of geothermal systems suitable for the exploration, operational and closure phases of mine development. The geothermal opportunities associated with abandoned or legacy mines are also discussed. The potential categories of heat reservoirs associated with mine sites are: natural ground; backfilled workings; mine waste; dewatering pumping; and flooded workings/pit lakes. The potentially lower operational costs for heating and cooling must be offset against the capital cost of a geothermal system. The focus for mine operators should therefore be on identifying at feasibility stage those projects where conditions are favourable for geothermal systems, the potential risks are understood, the economics are likely to be beneficial, and geothermal systems can be established while minimising additional capital costs

Synthesis of knowledge on the effects of fire and fire surrogates on wildlife in US dry forests

Summary: Dry forests throughout the United States are fire-dependent ecosystems, and much attention has been given to restoring their ecological function. As such, land managers often are tasked with reintroducing fire via prescribed fire, wildland fire use, and fire-surrogate treatments such as thinning and mastication. During planning, managers frequently are expected to anticipate effects of management actions on wildlife species. This document represents a synthesis of existing knowledge on wildlife responses to fire and fire-surrogate treatments, presented in a useful, management-relevant format. Based on scoping meetings and dialogue with public lands managers from throughout the United States, we provide detailed, species-level, summary tables for project biologists and fire managers trying to anticipate the effects of fire and fire-surrogate treatments on local wildlife species

Desire to change one's multimodality and its relationship to the use of different transport means

Using data collected from French employees of a transportation institute and residents of the US San Francisco Bay Area, we operationalize a segmentation of mobility patterns based on objective, subjective, and desired amounts of mobility by various modes and overall. We especially focus on the degree of multimodality in an individual's current modal mix and desired changes to that mix through the use of a "multimodality index". The clusters that result showed some similarities and some differences across countries, where the latter are likely due to disparities in the sampling strategies and in the land use/transportation/cultural milieux. In both cases, however, the clusters have useful policy implications, enabling us, for example, to distinguish car users who might be inclined to reduce car use and increase transit use from those who are largely content with their current modal basket

Elementary excitations in antiferromagnetic Heisenberg systems

The structure of the (eigen)states of antiferromagnetic Heisenberg systems is discussed. These systems are shown to be equivalent to classical systems of coupled harmonic oscillators. Most attention will be paid to the first excited state. This state is supposed to be a triplet. An approximation method, which is a generalization of a method, used to describe the ground state of Heisenberg systems, will be used to describe elementary excitations. The working of the method is demonstrated by some small-system calculations

Mussel eggs as indicators of mutagen exposure in coastal and estuarine environments

The aim of this study was to develop a short-term genotoxicity assay for monitoring the marine environment for mutagens. Based on the developing eggs and embryos of the marine mussel Mytilus edulis, an important pollution indicator species, the test employs the sensitive sister chromatid exchange (SCE) technique as its end-point, and exploits the potential of mussel eggs to accumulate mutagenic pollutants from the surrounding sea water. Mussel eggs take up to 6 months to develop while in the gonad, which provides scope for DNA damage to be accumulated over an extended time interval; chromosome damage is subsequently visualised as SCEs in 2-cell-stage embryos after these have been spawned in the laboratory. Methods which measure biological responses to pollutant exposure are able to integrate all the factors (internal and external) which contribute to the exposure. The new cytogenetic assay allows the effects of adult exposure to be interpreted in cells destined to become part of the next generation

Water hyacinth infestation: nuisance or nugget

(11 page document

Results on dust storms and stationary waves in three Mars years of data assimilation

Not available