Ferrovial (United Kingdom)

Selecting the most appropriate dimension stones has always been one of the vital issues in processing plants which stone is processing. This study aims to develop a new hierarchical model to evaluate and rank the dimension stone with the use of effective and major criteria such as beauty and durability, stone slab ability, supply chain, profitability, domestic and foreign market demand, and environmental factors and simultaneously, considering subjective judgments of decision-makers. The proposed approach is based on the fuzzy Delphi analytic hierarchy process method to calculate the effectiveness of the criteria and rank the dimension stone by decision-makers. This model is utilized for some stone process plants to assess and rank some famous Iranian granite. Then, the most appropriate stones for stone processing process plants are ranked. The ranking results showed that Chayan black granite with a 0.24 value, is the best stone to sawing in studied stone process plants. Finally, it was deduced that the most appropriate selection of dimension stone can reliably be done using the developed approach according to the most important effective criteria.

Only one transformer and two power switches are needed to implement a DPx dc-dc converter with constant gain (DCx). Both primary and secondary switches are ON and OFF simultaneously, connecting input and output through the transformer. At turn on, the leakage inductance limits the current transition to its steady state within the switching cycle, where it stays for a duty cycle higher than 50% featuring low rms current in the power switches. During the OFF time the transformer is reset, by a resonance between magnetizing inductance and the capacitance (parasitic and added) in parallel with the switches. It features 1-cycle dynamics and no-load operation. Bi-directional power flow and multiple outputs are straightforward. Excellent performance is obtained for 48 to 4V and 12 to IV dc-dc converters to supply high performance processors which may be extended to other gains as 48 to IV, just changing the transformer turns ratio

Os melhoramentos do sistema de navegação fluvial, aliado ao ferroviário e portuário, fariam parte da necessidade do governo imperial em criar vias de locomoção para o transporte de mercadorias e pessoas. Para tal era necessário o conhecimento dos rios e dos dois sistemas em pontos estratégicos.Para atender a demanda de reformas foram organizadas comissões, uma delas foi a Comissão de Melhoramento do Rio São Francisco (CMRSF) 1883-1896. A CMRSF foi criada para executar melhorias no Rio Com objetivo de facilitar a navegação e por em prática os melhoramentos do rio a partir dos estudos feitos pela CHI(Comissão Hidráulica do Imperio ). A comissão foi composta por engenheiros brasileiros aproveitando, inclusive, alguns que trabalharam na CHI. A primeira equipe foi chefiada pelo Antonio Plácido Peixoto do Amarante com a participação dos engenheiros Theodoro Fernandes Sampaio, João Emiliano Amarante, Evaristo Galvão Filho, João Felix Peixoto de Azevedo Sobrinho, Themístocles Pompeu de Albuquerque Figueiredo, Brotero Frederico de Macedo Costa, Antônio Julio de Gouvêa, além do médico Guilherme Lassance Marback.A história dos mapas é mais antiga que a própria história, isto se pensarmos na história como a documentação escrita sobre fatos passados. A confecção de mapas precede a escrita. Isto pode ser concluído como fato comprovado, por muitos exploradores dos vários povos primitivos que, embora eles não houvessem alcançado a fase da escrita, desenvolveram habilidades de traçar mapas.O objetivo da cartografia consiste em reunir e analisar dados e medidas das diversas regiões da terra, e representar graficamente em escala reduzida os elementos da configuração que possam ser claramente visíveis. Para pôr em evidência a configuração da superfície terrestre, o instrumento principal do cartografo é o mapa.Os mapas escolhidos para tal pesquisa têm características similares. Feitos à mão por Theodoro, num papel de linhas horizontais e verticais, representam respectivamente paralelos meridianos. Os mapas traziam os detalhamentos e as orientações necessárias à implementação técnica dos projetos propostos.

O advento ferroviário foi um dos principais fatores para a expansão do capitalismo industrial. No Brasil, onde a implantação esteve diretamente associada ao escoamento da produção agrícola, galgou maior importância no auge do modelo agrárioexportador. A partir do início do processo de industrialização, sua relevância econômica foi paulatinamente atenuada, atingindo alto grau de deterioração no início da década de 1990, quando a quase totalidade da malha ferroviária brasileira foi privatizada. Desde então, os investimentos, públicos e privados, foram lentamente retomados. Nesse sentido, este trabalho tem por objetivo resgatar os principais momentos históricos pelos quais passou o fenômeno ferroviário no Brasil desde suas origens até a contemporaneidade.

Dix ans après sa découverte, nous tentons un premier bilan concernant cette forme fluviale qu’est le lit majeur exceptionnel, en faisant la part entre les connaissances et les ignorances. Actuellement, cette forme a été reconnue dans deux domaines climatiques distincts : le domaine méditerranéen et le domaine tropical sec, mais elle n’a été réellement étudiée et échantillonnée que dans le Midi méditerranéen français et en Tunisie aride. Dans la perspective du risque d’inondation, il est nécessaire de distinguer le lit majeur exceptionnel à la fois du lit majeur ordinaire et des terrasses alluviales holocènes. L’étude de la bibliographie montre qu’il a probablement été souvent confondu avec la « basse terrasse inondable » sur de nombreux cours d’eau et dans des domaines climatiques variés. Les analyses réalisées sur plusieurs secteurs d'études, permettent de préciser certaines caractéristiques de ces formes inondables.

The management of marine fisheries needs to undergo dramatic change in the new millennium, in response to the well-documented evidence of global overfishing and the general depletion of commercial fish stocks. The axioms of sustainable development and equilibrium productivity of wild ecosystems are identified as misleading concepts, which nonetheless underlie current approaches to the management of living marine resources. Current trends in marine fisheries landings worldwide provide little evidence of sustainability of marine resources under current management paradigms, where biological, economic and social aspects of fisheries are usually treated as different disciplines. While open-access conditions are less widespread than formerly, except for many straddling and highly migratory resources, fishers usually have access to the resource year-round throughout its range. Despite quotas, the nominal control of capacity and technical measures protecting juveniles, top-down management has generally been unable to prevent stock depletion, particularly of the older spawners that for demersal stocks often support recruitment. An integrated solution to the complexity of managing wild resources seems not to have been achieved. Any new paradigm should assert the basic unpredictability of fisheries at the system level and require a broader range of performance indicators to be incorporated into the decisional framework. This must reflect the non-equilibrium nature of marine systems, and give greater importance to resource (as opposed to harvest) continuity in the face of regime shifts, and promote habitat restoration and conservation of genetic resources. The new management framework requires co-management and collective decision-making to be incorporated within a precautionary and pre-negotiated management framework. This must explicitly recognize that decision-making occurs in conditions of model-based uncertainty and precautionary approaches should be incorporated at all levels, not least of which is to avoid the assumption that all resources can be harvested in a sustainable fashion through time. Redundancy in data inputs to management are needed to avoid the surprises that model-based sampling occasionally leads to, for example, when regime changes reduce productivity in response to climatic fluctuations. Emergency frameworks imposing non-discretionary rules must be invoked when overfishing and/or regime change trigger reference points indicating stock depletion. Non-discretionary recovery plans should then override rights-based systems and persist until fish populations recover to pre-established healthy levels, which may in turn need to await the return of a favourable regime. In fact, some stocks may require periodic rebuilding after regime-induced collapses or because of a combination of ecological or economic impacts, hence a constant harvest policy may not always be possible. It will probably also be necessary to discard the axiom that a stock should be available to harvesting throughout its range and seasonal cycle. Technological advances mean that time- and area-specific access rights are now practical options, through satellite monitoring of vessel operations, even offshore. More fundamentally, the basic axiom of "enlightened self interest" underlying current methods of management will need to be tempered by an increased ethical concern for the fragility of natural ecosystems.

Abstract Investigation of the damping mechanisms of metals and alloys requires that damping capacity measurements be made over wide stress, frequency, and temperature ranges. The torsion pendulum described herein fulfills these requirements in all respects except that it has a limited (low) frequency range. This versatile apparatus also allows creep, fatigue, stress relaxation, elastic after-effect, static and dynamic moduli and hysteresis curves to be made at temperature and in vacuo. It is possible to superimpose a magnetic field on the specimen during these measurements. The specimen may also be heat treated or plastically deformed in situ. An electronic data processing system has been designed to calculate and plot material damping characteristics during a free decay test. The damping characteristics are thus obtained more quickly and with greater accuracy than was previously possible.