18,598 research outputs found
A technological solution for everywhere energy supply
The hydrogen economy is still at the beginning, but society innovation, and the market push inexorably toward hydrogen, inspiring the idea to build an energy-integrated system that can satisfy, in an independent way, the energy needs of small-sized consumers. The technologies used for the system design are already available in the market and, at least for the standard Solutions, sufficiently mature. The innovation consists of an integration, optimization, and industrialization of this modular system, which is an electric zero-emissions generator giving 3.5 kW(p) as an output power This is the only system able to produce its own fuel, guaranteeing renewable and clean energy., available where and when you want. This system is constituted by a polymer membrane electrolyzer, a metal hydrides tank (which absorbs and desorbs hydrogen), and a polymer fuel cell (PEM). The system modularity can also satisfy higher energy requirements, and the low-pressure hydrogen storage system through metal hydrides guarantees the system safety.
(ASME Transactions
The CLAWAR project
In Europe, there are two main thematic groups focusing on
robotics, the Climbing and Walking Robots (CLAWAR)
project (http://www.clawar.net) and the European Robotics
Network (EURON) project (http://www.euron.org).
The two networks are complementary: CLAWAR is
industrially focused on the immediate needs, and EURON is
focused more on blue skies research. This article presents the activities of the CLAWAR project
The CLAWAR project
In Europe, there are two main thematic groups focusing on
robotics, the Climbing and Walking Robots (CLAWAR)
project (http://www.clawar.net) and the European Robotics
Network (EURON) project (http://www.euron.org).
The two networks are complementary: CLAWAR is
industrially focused on the immediate needs, and EURON is
focused more on blue skies research. This article presents the activities of the CLAWAR project
Problem solving and the co-ordination of innovative activities
In the context of increasingly globalized markets, ever more complex supply chains and international manufacturing networks, corporate decision-making processes involve more and more actors, variables and criteria. This is a challenge for corporate head quarters. Many have argued that the role once attributed to the integrated innovative organisation and its R&D laboratories is increasingly associated with the functioning of networks of specialised innovators. The aim of this paper is to argue that the role of large firms may have changed, but it is far from disappeared. It looks at the interplay of increasing knowledge specialisation, the development of products of increasing complexity that perform a widening range of functionalities, and the emergence and diffusion of new design strategies for both products and organisations, namely modularity. The emergence of modularity as a product and organisational design strategy is clearly connected to recent trends in organisational design. Modularity would allow the decoupling of complex artifacts into simpler, self-contained modules. Each module would, at the extreme, become the sole business of a specialised trade. This paper builds upon the idea that there are cognitive limits to this process of modularisation: what kinds of problems firms solve, and how they solve them, set limits to the extent of division of labour among firms. We draw implications of such limits for both management and economic theory.large firms, knowledge specialisation, complex products, modularity,
The compositional and evolutionary logic of metabolism
Metabolism displays striking and robust regularities in the forms of
modularity and hierarchy, whose composition may be compactly described. This
renders metabolic architecture comprehensible as a system, and suggests the
order in which layers of that system emerged. Metabolism also serves as the
foundation in other hierarchies, at least up to cellular integration including
bioenergetics and molecular replication, and trophic ecology. The
recapitulation of patterns first seen in metabolism, in these higher levels,
suggests metabolism as a source of causation or constraint on many forms of
organization in the biosphere.
We identify as modules widely reused subsets of chemicals, reactions, or
functions, each with a conserved internal structure. At the small molecule
substrate level, module boundaries are generally associated with the most
complex reaction mechanisms and the most conserved enzymes. Cofactors form a
structurally and functionally distinctive control layer over the small-molecule
substrate. Complex cofactors are often used at module boundaries of the
substrate level, while simpler ones participate in widely used reactions.
Cofactor functions thus act as "keys" that incorporate classes of organic
reactions within biochemistry.
The same modules that organize the compositional diversity of metabolism are
argued to have governed long-term evolution. Early evolution of core
metabolism, especially carbon-fixation, appears to have required few
innovations among a small number of conserved modules, to produce adaptations
to simple biogeochemical changes of environment. We demonstrate these features
of metabolism at several levels of hierarchy, beginning with the small-molecule
substrate and network architecture, continuing with cofactors and key conserved
reactions, and culminating in the aggregation of multiple diverse physical and
biochemical processes in cells.Comment: 56 pages, 28 figure
A design study of a 350 kWe out-of-core nuclear thermionic converter system
Out-of-core nuclear thermionic converter system for high power level
Community Structure of the Physical Review Citation Network
We investigate the community structure of physics subfields in the citation
network of all Physical Review publications between 1893 and August 2007. We
focus on well-cited publications (those receiving more than 100 citations), and
apply modularity maximization to uncover major communities that correspond to
clearly-identifiable subfields of physics. While most of the links between
communities connect those with obvious intellectual overlap, there sometimes
exist unexpected connections between disparate fields due to the development of
a widely-applicable theoretical technique or by cross fertilization between
theory and experiment. We also examine communities decade by decade and also
uncover a small number of significant links between communities that are widely
separated in time.Comment: 14 pages, 7 figures, 8 tables. Version 2: various small additions in
response to referee comment
A path to in-space welding and to other in-space metal processing technologies using Space Shuttle small payloads
As we venture into space, it becomes necessary to assemble, expand, and repair space-based structures for our housing, research, and manufacturing. The zero gravity-vacuum of space challenges us to employ construction options which are commonplace on Earth. Rockwell International (RI) has begun to undertake the challenge of space-based construction via numerous options, of which one is welding. As of today, RI divisions have developed appropriate resources and technologies to bring space-based welding within our grasp. Further work, specifically in the area of developing space experiments to test RI technology, is required. RI Space Welding Project's achievements to date, from research and development (R&E) efforts in the areas of microgravity, vacuum, intra- / extra- vehicular activity and spinoff technologies, are reviewed. Special emphasis is given to results for G-169's (Get Away Special) microgravity flights aboard a NASA KC-135. Based on these achievements, a path to actual development of a space welding system is proposed with options to explore spinoff in-space metal processing technologies. This path is constructed by following a series of milestone experiments, of which several are to utilize NASA's Shuttle Small Payload Programs. Conceptual designs of the proposed shuttle payload experiments are discussed with application of lessons learned from G-169's design, development, integration, testing, safety approval process, and KC-135 flights
Technologies and strategies to design sustainable tourist accommodations in areas of high environmental value not connected to the electricity grid
As envisaged in the Agenda for a sustainable and competitive European tourism, the adoption of an holistic and integrated approach and the use of the best available knowledge and technologies are key aspects to ensure a sustainable tourism. In particular, policies and actions should be planned considering the latest and best available knowledge, analyzing at the same time all the related impacts on the area of intervention.
In this context, the purpose of this paper is to describe an approach for designing sustainable tourist accommodations that allow the fruition of areas characterized by high environmental values minimizing the related impacts on the surrounding environment and sensitizing users towards preservation and conservation of natural resources.
In the proposed approach three aspects of tourist accommodation have been considered: the system component, the building envelope and the integration between them.
As a result, the architectural structures designed, including their materials, shape, energy efficiency, modularity and removability, are in line with the standards of bio-architecture.
The materials used, complying with the technical requirements and the technological needs of the tourist accommodations, are mostly recycled or reusable, coming from the surrounding area or of easy integration in the landscape.
The components , that constitute the accommodations, are easy to assemble and disassemble for reuse them in another area, without changing the environmental conditions in the site. Some elements are precast and completed on site with local materials, moreover the modularity allows a high adaptability to different environmental and morphological conditions.
To apply these architectural structures even in places without services and distribution networks of energy and water, special attention has been given to innovative and sustainable energy solutions: Liquefied petroleum gas (LPG) has been used as the only energy vector, combined with a cogeneration plant to provide heat and electric energy as well as with particular building envelopes that allow the transfer of LPG into the walls for provide energy to innovative gas appliances. Lastly, in order to assess the environmental impact of the proposed approach, it has been analyzed the environmental insertion of these structures for tourist accommodation in the Circeo National Park, in Italy
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