66 resultados para Rotors -- Balancing


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Over 1 million km2 of seafloor experience permanent low-oxygen conditions within oxygen minimum zones (OMZs). OMZs are predicted to grow as a consequence of climate change, potentially affecting oceanic biogeochemical cycles. The Arabian Sea OMZ impinges upon the western Indian continental margin at bathyal depths (150 - 1500 m) producing a strong depth dependent oxygen gradient at the sea floor. The influence of the OMZ upon the short term processing of organic matter by sediment ecosystems was investigated using in situ stable isotope pulse chase experiments. These deployed doses of 13C:15N labeled organic matter onto the sediment surface at four stations from across the OMZ (water depth 540 - 1100 m; [O2] = 0.35 - 15 μM). In order to prevent experimentally anoxia, the mesocosms were not sealed. 13C and 15N labels were traced into sediment, bacteria, fauna and 13C into sediment porewater DIC and DOC. However, the DIC and DOC flux to the water column could not be measured, limiting our capacity to obtain mass-balance for C in each experimental mesocosm. Linear Inverse Modeling (LIM) provides a method to obtain a mass-balanced model of carbon flow that integrates stable-isotope tracer data with community biomass and biogeochemical flux data from a range of sources. Here we present an adaptation of the LIM methodology used to investigate how ecosystem structure influenced carbon flow across the Indian margin OMZ. We demonstrate how oxygen conditions affect food-web complexity, affecting the linkages between the bacteria, foraminifera and metazoan fauna, and their contributions to benthic respiration. The food-web models demonstrate how changes in ecosystem complexity are associated with oxygen availability across the OMZ and allow us to obtain a complete carbon budget for the stationa where stable-isotope labelling experiments were conducted.

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We consider how in issue selling, subsidiaries draw on different forms of legitimacy to attract corporate headquarters’ (CHQ) positive attention and minimise negative CHQ attention. Through case study evidence, we find that directing CHQ attention to subsidiary issues needs to be executed as a balancing act through forms of subsidiary legitimacy, namely; the personal legitimacy of key individuals at the subsidiary; consequential legitimacy vis-à-vis peer subsidiaries; and linkage legitimacy in the local environment. We develop a typology of subsidiary issue-selling roles and illustrate how negative CHQ attention results from a failure to legitimise issue selling.

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While the right of parents to educate their children in their religious or philosophical conviction is recognised in Human Rights instruments (e.g. CoE 1952, protocol 1), educators must also attend to the right of a child to autonomy (UN 1989, Article 12.1) and the right of liberal democratic states to reproduce values of equity and freedom. This paper argues that certain forms of inter-religious dialogue and/or inter-religious collaborative learning can assist educators in balancing these rights where religion has significant influence and power over the management of schools and/or the curriculum. It is argued that in addition to the learning benefits which may result, the use of collaboration and dialogue goes some way in addressing three philosophical criticisms of religious education: first that religiously separate and religiously based education pays insufficient attention to the rights of children and, secondly, is likely to contribute to social fragmentation; and third, pupils will lack the skills to overcome prejudice or intolerance where they have no experience of others as a result of separate schooling or from a religiously narrow curriculum, and the latter may in fact support intolerant views. A rationale is developed that asserts the value of collaboration or dialogue as a pedagogical strategy that can, to some degree, mitigate potential negative outcomes from religious education. This argument is further supported with reference to a range of empirical studies.

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This article considers how the education systems of divided societies have been shaped in response to the experience of ethnic and religious conflict. The analysis identifies two competing priorities in such contexts – the development of social cohesion and the protection of cultural, ethnic and religious identities - and explores how these may be reconciled through a model of ‘shared education’. Drawing on research evidence and recent experience of shared education in relation to Northern Ireland, the Former Yugoslav Republic of Macedonia and Cyprus, we reflect on the advantages and challenges of this model in areas experiencing conflict and division.

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Relative Evidential Supports (RES) was developed and justified several years ago as a non-numeric apparatus that allows us to compare evidential supports for alternative conclusions when making a decision. An extension called Graded Relative Evidence (GRE) of the RES concept of pairwise balancing and trading-off of evidence is reported here which keeps its basic features of simplicity and perspicacity but enriches its modelling fidelity by permitting very modest and intuitive variations in degrees of outweighing (which the essentially binary RES does not). The formal justification is very simply based on linkages to RES and to the Dempster - Shafer theory of evidence. The use of the simple extension is illustrated and to a small degree further justified empirically by application to a topical scientific debate about what is called the Congo Crossover Conjecture here. This decision-making instance is chosen because of the wealth of evidence that has been accumulated on both sides of the debate and the range of evidence strengths manifested in it. The conjecture is that the advent of Aids was in the late 1950s in the Congo when a vaccine for polio was allegedly cultivated in the kidneys of chimpanzees which allowed the Aids infection to cross over to humans from primates. © 2005 Springer.

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Abstract To achieve higher flexibility and to better satisfy actual customer requirements, there is an increasing tendency to develop and deliver software in an incremental fashion. In adopting this process, requirements are delivered in releases and so a decision has to be made on which requirements should be delivered in which release. Three main considerations that need to be taken account of are the technical precedences inherent in the requirements, the typically conflicting priorities as determined by the representative stakeholders, as well as the balance between required and available effort. The technical precedence constraints relate to situations where one requirement cannot be implemented until another is completed or where one requirement is implemented in the same increment as another one. Stakeholder preferences may be based on the perceived value or urgency of delivered requirements to the different stakeholders involved. The technical priorities and individual stakeholder priorities may be in conflict and difficult to reconcile. This paper provides (i) a method for optimally allocating requirements to increments; (ii) a means of assessing and optimizing the degree to which the ordering conflicts with stakeholder priorities within technical precedence constraints; (iii) a means of balancing required and available resources for all increments; and (iv) an overall method called EVOLVE aimed at the continuous planning of incremental software development. The optimization method used is iterative and essentially based on a genetic algorithm. A set of the most promising candidate solutions is generated to support the final decision. The paper evaluates the proposed approach using a sample project.

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WebCom-G is a fledgling Grid Operating System, designed to provide independent service access through interoperability with existing middlewares. It offers an expressive programming model that automatically handles task synchronisation – load balancing, fault tolerance, and task allocation are handled at the WebCom-G system level – without burdening the application writer. These characteristics, together with the ability of its computing model to mix evaluation strategies to match the characteristics of the geographically dispersed facilities and the overall problem- solving environment, make WebCom-G a promising grid middleware candidate.

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Hypoxia-inducible factor (HIF) a, which has three isoforms, is central to the continuous balancing of the supply and demand of oxygen throughout the body. HIF-a is a transcription factor that modulates a wide range of processes, including erythropoiesis, angiogenesis, and cellular metabolism. We describe a family with erythrocytosis and a mutation in the HIF2A gene, which encodes the HIF-2a protein. Our functional studies indicate that this mutation leads to stabilization of the HIF-2a protein and suggest that wild-type HIF-2a regulates erythropoietin production in adults.

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The hydroformylation of 1-octene under continuous flow conditions is described. The system involves dissolving the catalyst, made in situ from [ Rh(acac)(CO)(2)] (acacH = 2,4- pentanedione) and [RMIM][TPPMS] ( RMIM = 1-propyl (Pr), 1-pentyl (Pn) or 1-octyl (O)-3-methyl imidazolium, TPPMS = Ph2P(3-C6H4SO3)), in a mixture of nonanal and 1-octene and passing the substrate, 1-octene, together with CO and H-2 through the system dissolved in supercritical CO2 (scCO(2)). [PrMIM][TPPMS] is poorly soluble in the medium so heavy rhodium leaching (as complexes not containing phosphine) occurs in the early part of the reaction. [PnMIM][ PPMS] affords good rates at relatively low catalyst loadings and relatively low overall pressure (125 bar) with rhodium losses <1 ppm, but the catalyst precipitates at higher catalyst loadings, leading to lower reaction rates. [OMIM][ TPPMS] is the most soluble ligand and promotes high reaction rates, although preliminary experiments suggested that rhodium leaching was high at 5-10 ppm. Optimisation aimed at balancing flows so that the level within the reactor remained constant involved a reactor set up based around a reactor fitted with a sight glass and sparging stirrer with the CO2 being fed by a cooled head HPLC pump, 1-octene by a standard HPLC pump and CO/H-2 through a mass flow controller. The pressure was controlled by a back pressure regulator. Using this set up, [OMIM][ TPPMS] as the ligand and a total pressure of 140 bar, it was possible to control the level within the reactor and obtain a turnover frequency of ca. 180 h(-1). Rhodium losses in the optimised system were 100 ppb. Transport studies showed that 1-octene is preferentially transported over the aldehydes at all pressures, although the difference in mol fraction in the mobile phase was less at lower pressures. Nonanal in the mobile phase suppresses the extraction of 1-octene to some extent, so it is better to operate at high conversion and low pressure to optimise the extraction of the products relative to the substrate. CO and H2 in the mobile phase also suppress the extraction effciency by as much as 80%.

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Invasive species and environmental change often occur simultaneously across a habitat and therefore our understanding of their relative roles in the decline of native species is often poor. Here, the environmental mediation of a critical interspecific interaction, intraguild predation (IGP), was examined between invasive (Gammarus pulex) and native (G. d. celticus) freshwater amphipods. In the laboratory, IGP asymmetries (males preying on congeneric females) were examined in river water sourced from zones where: (1) the invader has completely displaced the native; (2) the two species currently co-exist, and (3) the native currently persists uninvaded. The invader was always a more effective IG predator, but this asymmetry was significantly weaker moving from 'invader-only water' through 'co-existence water' to 'native-only water'. The constituent of the water that drives this mediation of IGP was not identified. However, balancing the rigour of laboratory experiments with field derived 'environment' has advanced understanding of known patterns in a native species decline, and its co-existence and persistence in the face of an invader.

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In the last decade, data mining has emerged as one of the most dynamic and lively areas in information technology. Although many algorithms and techniques for data mining have been proposed, they either focus on domain independent techniques or on very specific domain problems. A general requirement in bridging the gap between academia and business is to cater to general domain-related issues surrounding real-life applications, such as constraints, organizational factors, domain expert knowledge, domain adaption, and operational knowledge. Unfortunately, these either have not been addressed, or have not been sufficiently addressed, in current data mining research and development.Domain-Driven Data Mining (D3M) aims to develop general principles, methodologies, and techniques for modeling and merging comprehensive domain-related factors and synthesized ubiquitous intelligence surrounding problem domains with the data mining process, and discovering knowledge to support business decision-making. This paper aims to report original, cutting-edge, and state-of-the-art progress in D3M. It covers theoretical and applied contributions aiming to: 1) propose next-generation data mining frameworks and processes for actionable knowledge discovery, 2) investigate effective (automated, human and machine-centered and/or human-machined-co-operated) principles and approaches for acquiring, representing, modelling, and engaging ubiquitous intelligence in real-world data mining, and 3) develop workable and operational systems balancing technical significance and applications concerns, and converting and delivering actionable knowledge into operational applications rules to seamlessly engage application processes and systems.

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This paper addresses the problems often faced by social workers and their supervisors in decision making where human rights considerations and child protection concerns collide. High profile court cases in the United Kingdom and Europe have consistently called for social workers to convey more clarity when justifying their reasons for interfering with human rights in child protection cases. The themes emerging from these case law decisions imply that social workers need to be better at giving reasons and evidence in more explicit ways to support any actions they propose which cause interference with Convention Rights. Toulmin (1958, 1985) offers a structured approach to argumentation which may have relevance to the supervision of child protection cases when social workers and managers are required to balance these human rights considerations. One of the key challenges in this balancing act is the need for decision makers to feel confident that any interventions resulting in the interference of human rights are both justified and proportionate. Toulmin’s work has already been shown to have relevance for assisting social workers navigate pathways through cases involving competing ethical and moral demands (Osmo and Landau, 2001) and more recently to human rights and decision making in child protection (Duffy et al, 2006). Toulmin’s model takes the practitioner through a series of stages where any argument or proposed recommendation (claim) is subjected to intense critical analysis involving exposition of its strengths and weaknesses. The author therefore proposes that explicit argumentation (Osmo and Landau, 2001) may help supervisors and practitioners towards safer and more confident decision making in child protection cases involving the interference of the human rights of children and parents. In addition to highlighting the broader context of human rights currently permeating child protection decision making, the paper will include case material to practically demonstrate the application of Toulmin’s model of argumentation to the supervision context. In this way the paper adopts a strong practice approach in helping to assist practitioners with the problems and dilemmas they may come up against in decision making in complex cases.

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Whilst the project to increase workforce mobility is part of a common labour force policy across the European Union, for some social workers, it has also been coupled with an aspiration to develop a pan-European identity within the profession (Lorenz, 1994, 2000; Frost, 2008). In this article, taking the island of Ireland as an example, we examine empirical data on the movement of social workers in recent years, both within Ireland and inward from outside the island, and consider the challenges and opportunities this has presented for the profession, also drawing on the British experience. From this analysis, some tentative conclusions are drawn about what is happening, what is possible and what is desirable in balancing aspirations for increased mobility within the European Union and a pan-European social work identity against the needs and interests of local, European and global communities.