21 resultados para Scientific and technical aerospace reports
em Aston University Research Archive
Resumo:
Every year throughout the world, individuals' health is damaged by their exposure to toxic chemicals at work. In most cases these problems will resolve, but many will sustain permanent damage. Whilst any justified claim for compensation requires medical and legal evidence a crucial and often controversial component of this process is the establishment of a causal link between the individual's condition and exposure to a specific chemical or substance. Causation, in terms of how a substance or substances led the claimant to his or her current plight, can be difficult to establish and the main purpose of this book, is to provide the aspiring expert report writer with a concise, practical guide that uses case histories to illuminate the process of establishing causation in occupational toxicity proceedings. In summary: A practical, accessible guide to the preparation of balanced, scientifically sound expert reports in the context of occupational toxicology. Focuses on the scientist's role in establishing a causal link between exposure to toxins and an individual's ill health. Includes real-life case histories drawn from the Author's 15 years experience in this area to illustrate the principles involved. Expert Report Writing in Toxicology: Forensic, Scientific and Legal Aspects proves invaluable to scientists across a range of disciplines needing guidance as to what is expected of them in terms of the best use of their expertise and how to present their findings in a manner that is authoritative, balanced and informative.
Resumo:
The paper examines howfar foreign manufacturing investment in UK industries, together with the spatial agglomeration of those industries, affect technical efficiency. The paper links research on the estimation of technical efficiency,with those literatures demonstrating the economies associated with foreign direct investment and spatial agglomeration. The methodology involves estimation of a stochastic production frontier with random components associated with industry technical inefficiency, and a standard error. The paper also explores whether the degree of foreign involvement has a greater impact on technical efficiency where the domestic industry sector is characterized by comparatively high productivity and spatial agglomeration. The policy implications of the analysis are discussed.
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This paper extends the existing evidence on the relationship between Information and Communication Technology (ICT) and productivity using data from the entire Iranian manufacturing sector (22 industries) over the period 1993?1999. Estimates of efficiency using panel data confirm the positive and significant impact of ICT investments on productivity. Our finding is consistent with the most recent literatures in the context of developed and a few middle-income developing countries. Human capital and increasing ICT capital are probably two determining factors in gaining the positive payoffs from ICT investments in Iran.
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In 1957, Farrell proposed to measure technical (in)efficiency as the realised deviation from a frontier isoquant. Since then, the research has developed several methods to derive the production frontier and it has also extended its scope in applying frontier techniques to the measurement of total factor productivity. In this paper, I present the core techniques for the measurement of technical efficiency and productivity based on the notion of frontier and introduce the more recent technological advances in the field.
Resumo:
The purpose of this paper is to analyse the relationship between the corporate governance system and technical efficiency in Italian manufacturing. We use a non-parametric frontier technique (DEA) to derive technical efficiency measures for a sample of Italian firms taken from nine manufacturing industries. These measures are then related to the characteristics of the corporate governance system. Two of these characteristics turn out to have a positive impact on technical efficiency: the percentage of the company shares owned by the largest shareholder and the fact that a firm belongs to a pyramidal group. Interestingly, a trade-off emerges between these influences, in the sense that one is stronger in industries where the other is weaker. Copyright © 2007 John Wiley & Sons, Ltd.
Resumo:
This paper tries to identify under which conditions increasing market competition may help cooperatives to improve technical efficiency to guarantee positive profits. This hypothesis is first formalized in a partial equilibrium framework and then is tested on a sample of Italian conventional and cooperative firms, using frontier analysis. Technical efficiency indexes are computed by using the one-stage approach as suggested by Battese and Coelli (1995), where proxies for competition are introduced as determinants of efficiency, along with other exogenous factors accounting for the firms’ heterogeneity. However, the overall impact of increasing competition on efficiency is negative.
Resumo:
This thesis follows the argument that, to fully understand the current position of national research laboratories in Great Britain one needs to study the historical development of the government research establishment as a specific social institution. A particular model is outlined in which it is argued that institutional characteristics evolve through the continual interplay between internal development and environmental factors within a changing political and economic context, and that the continuous development of an institution depends on its ability to adapt to changes in its operational environment. Within this framework important historical precedents for formal government institutional support for applied research are identified. and the transition from private to public patronage documented. The emergence and consolidation of government research laboratories in Britain is described in detail. The subsequent relative decline of public laboratories is interpreted in terms of the undermining of a traditional role resulting in legitimation crisis. It is concluded that it is no longer feasible to consider the public research laboratory as a coherent institutional form, and that the future of each individual laboratory can only be considered in relation to the institutional needs of its own sphere of operation. Nevertheless the laboratories have been forced into decline in an essentially unplanned way which may have serious consequences for the maintenance of the scientific and technical infrastructures, necessary for material progress in the national context.
Resumo:
Activated sludge basins (ASBs) are a key-step in wastewater treatment processes that are used to eliminate biodegradable pollution from the water discharged to the natural environment. Bacteria found in the activated sludge consume and assimilate nutrients such as carbon, nitrogen and phosphorous under specific environmental conditions. However, applying the appropriate agitation and aeration regimes to supply the environmental conditions to promote the growth of the bacteria is not easy. The agitation and aeration regimes that are applied to activated sludge basins have a strong influence on the efficacy of wastewater treatment processes. The major aims of agitation by submersible mixers are to improve the contact between biomass and wastewater and the prevention of biomass settling. They induce a horizontal flow in the oxidation ditch, which can be quantified by the mean horizontal velocity. Mean values of 0.3-0.35 m s-1 are recommended as a design criteria to ensure best conditions for mixing and aeration (Da Silva, 1994). To give circulation velocities of this order of magnitude, the positioning and types of mixers are chosen from the plant constructors' experience and the suppliers' data for the impellers. Some case studies of existing plants have shown that measured velocities were not in the range that was specified in the plant design. This illustrates that there is still a need for design and diagnosis approach to improve process reliability by eliminating or reducing the number of short circuits, dead zones, zones of inefficient mixing and poor aeration. The objective of the aeration is to facilitate the quick degradation of pollutants by bacterial growth. To achieve these objectives a wastewater treatment plant must be adequately aerated; thus resulting in 60-80% of all energetic consummation being dedicated to the aeration alone (Juspin and Vasel, 2000). An earlier study (Gillot et al., 1997) has illustrated the influence that hydrodynamics have on the aeration performance as measure by the oxygen transfer coefficient. Therefore, optimising the agitation and aeration systems can enhance the oxygen transfer coefficient and consequently reduce the operating costs of the wastewater treatment plant. It is critically important to correctly estimate the mass transfer coefficient as any errors could result in the simulations of biological activity not being physically representative. Therefore, the transfer process was rigorously examined in several different types of process equipment to determine the impact that different hydrodynamic regimes and liquid-side film transfer coefficients have on the gas phase and the mass transfer of oxygen. To model the biological activity occurring in ASBs, several generic biochemical reaction models have been developed to characterise different biochemical reaction processes that are known as Activated Sludge Models, ASM (Henze et al., 2000). The ASM1 protocol was selected to characterise the impact of aeration on the bacteria consuming and assimilating ammonia and nitrate in the wastewater. However, one drawback of ASM protocols is that the hydrodynamics are assumed to be uniform by the use of perfectly mixed, plug flow reactors or as a number of perfectly mixed reactors in series. This makes it very difficult to identify the influence of mixing and aeration on oxygen mass transfer and biological activity. Therefore, to account for the impact of local gas-liquid mixing regime on the biochemical activity Computational Fluid Dynamics (CFD) was used by applying the individual ASM1 reaction equations as the source terms to a number of scalar equations. Thus, the application of ASM1 to CFD (FLUENT) enabled the investigation of the oxygen transfer efficiency and the carbon & nitrogen biological removal in pilot (7.5 cubic metres) and plant scale (6000 cubic metres) ASBs. Both studies have been used to validate the effect that the hydrodynamic regime has on oxygen mass transfer (the circulation velocity and mass transfer coefficient) and the effect that this had on the biological activity on pollutants such as ammonia and nitrate (Cartland Glover et al., 2005). The work presented here is one part to of an overall approach for improving the understanding of ASBs and the impact that they have in terms of the hydraulic and biological performance on the overall wastewater treatment process. References CARTLAND GLOVER G., PRINTEMPS C., ESSEMIANI K., MEINHOLD J., (2005) Modelling of wastewater treatment plants ? How far shall we go with sophisticated modelling tools? 3rd IWA Leading-Edge Conference & Exhibition on Water and Wastewater Treatment Technologies, 6-8 June 2005, Sapporo, Japan DA SILVA G. (1994). Eléments d'optimisation du transfert d'oxygène par fines bulles et agitateur séparé en chenal d'oxydation. PhD Thesis. CEMAGREF Antony ? France. GILLOT S., DERONZIER G., HEDUIT A. (1997). Oxygen transfer under process conditions in an oxidation ditch equipped with fine bubble diffusers and slow speed mixers. WEFTEC, Chicago, USA. HENZE M., GUJER W., MINO T., van LOOSDRECHT M., (2000). Activated Sludge Models ASM1, ASM2, ASM2D and ASM3, Scientific and Technical Report No. 9. IWA Publishing, London, UK. JUSPIN H., VASEL J.-L. (2000). Influence of hydrodynamics on oxygen transfer in the activated sludge process. IWA, Paris - France.
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There is an ongoing debate over the use of pharmaceutical excipients in medicines for children, triggered by the increased number of formulations suitable for this target patient population. Pharmaceutical excipients can be regarded as essential / necessary enablers in formulation development. These are materials other than the 'active pharmaceutical ingredient' which are added to the formulation to achieve a specific function1. This may include aiding in the processing or manufacture of the drug delivery system such as lubricants or flow aids, controlling the release of the active ingredient to achieve modified release, enhance patient acceptability by improving taste of medicines or to develop easily swallowed dosage forms.
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The Digital Observatory for Protected Areas (DOPA) has been developed to support the European Union’s efforts in strengthening our capacity to mobilize and use biodiversity data, information and forecasts so that they are readily accessible to policymakers, managers, experts and other users. Conceived as a set of web based services, DOPA provides a broad set of free and open source tools to assess, monitor and even forecast the state of and pressure on protected areas at local, regional and global scale. DOPA Explorer 1.0 is a web based interface available in four languages (EN, FR, ES, PT) providing simple means to explore the nearly 16,000 protected areas that are at least as large as 100 km2. Distinguishing between terrestrial, marine and mixed protected areas, DOPA Explorer 1.0 can help end users to identify those with most unique ecosystems and species, and assess the pressures they are exposed to because of human development. Recognized by the UN Convention on Biological Diversity (CBD) as a reference information system, DOPA Explorer is based on the best global data sets available and provides means to rank protected areas at the country and ecoregion levels. Inversely, DOPA Explorer indirectly highlights the protected areas for which information is incomplete. We finally invite the end-users of DOPA to engage with us through the proposed communication platforms to help improve our work to support the safeguarding of biodiversity.
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In this paper, we test the extent to which producers' cooperatives can experience an increase in technical efficiency following a tightening of financial constraints. This hypothesis is tested on a sample of Italian conventional and cooperative firms for the wine production and processing sector, using frontier analysis. The results support the hypothesis that increasing financial pressure can affect positively the cooperatives efficiency. Journal compilation © CIRIEC 2010.
Resumo:
This paper begins with the argument that within modern-day society, engineering has shifted from being the scientific and technical mainstay of industrial, and more recently digital change to become the most vital driver of future advancement. In order to meet the inevitable challenges resulting from this role, the nature of engineering education is constantly evolving and as such engineering education has to change. The paper argues that what is needed is a fresh approach to engineering education – one that is sufficiently flexible so as to capture the fast-changing needs of engineering education as a discipline, whilst being pedagogically suitable for use with a range of engineering epistemologies. It provides an overview of a case study in which a new approach to engineering education has been developed and evaluated. The approach, which is based on the concept of scholarship, is described in detail. This is followed by a discussion of how the approach has been put into practice and evaluated. The paper concludes by arguing that within today's market-driven university world, the need for effective learning and teaching practice, based in good scholarship, is fundamental to student success.
Resumo:
Policy issues which receive large inputs of scientific and technical information are frequently marred by acrimonious controversies between contributing experts. There are few if any examples of a public policy decision being based on a firm consensus of scientific and technical experts. Such a consensus is taken for granted by the `Rational' model of decision making and its derivatives. Comparing the dynamics of conflict in policy-relevant issues with those of conflict in `pure' science, one is struck by their great similarity. In both cases we witness examples of rhetorical statements about incompetence, conflicting interpretations of data, and interdisciplinary communication problems. Noting this similarity, this thesis attempts to answer the question, `Is there a similarity of cause: do the same causes lie at the roots of conflict in policy-relevant and policy-irrelevant science?' In answering this question this thesis examines recent controversies in a generally policy-irrelevant science - evolutionary biology. Three episodes of conflict are studied: the `Neutral Allele Theory', `Punctuated Equilibrium', and `Structuralist versus Functionalist approaches to evolution'. These controversies are analysed in terms of both Kuhn's account of scientific `crises' and Collingridge and Reeve's (1986) `Overcritical Model'. Comparing its findings with those of Collingridge and Reeve, this thesis concludes that, (a) there is a Kuhnian crisis in contemporary evolution theory and, (b) that common causes do lie at the roots of conflict in policy-relevant and policy-irrelevant science. Science has an inherent tendency to degenerate into acrimonious conflict but at the same time has mechanisms which eventually resolve such conflicts. Unfortunately, when science is incorporated into the policy arena these mechanisms are prevented from operating. This thesis reinforces Collingridge and Reeve's conclusion that science is of little use to policy.