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311.
312.
V. Pasqualini C. Pergent-MARTINI C. Fernandez G. Pergent 《International journal of remote sensing》2013,34(5):1167-1177
Airborne remote sensing is a useful tool for the production of biocenosis maps. The use of an image processing system, integrating bathymetric data, makes it possible to considerably refine the charting, through a layer of water of variable thickness and quality. Other limiting factors may have an impact on the quality of results. The identification of these factors makes it possible to propose a scale of reliability. Four examples of aerial teledetection surveys provide the basis for ( i ) assessing the reliability of the maps, ( ii ) determining the reasons for this variation in reliability, and ( iii ) using the scale as a means for assessing the reliability of a given map. The factors used are such that the reliability scale could subsequently be applied to the cartography of other marine assemblages. 相似文献
313.
Recent literature in the field of strategic management suggests that firms must learn to combine internal competencies and resources in order to achieve competitive advantages. This paper examines how firms employ slack resources to enhance the relationship between quality management (QM) and organisational learning to obtain sustainable competitive advantages. The findings use empirical data gathered from 202 quality managers to support the hypotheses that: (1) there is a strong connection between organisational learning and QM; and (2) the relation between organisational learning and QM is moderated by slack resources. 相似文献
314.
This paper shows how to embed complete binary trees in products of complete binary trees, products of shuffle‐exchange graphs,
and products of de Bruijn graphs with small dilation and congestion. In the embedding results presented here the size of the
host graph can be fixed to an arbitrary size, while we define no bound on the size of the guest graph. This is motivated by
the fact that the host architecture has a fixed number of processors due to its physical design, while the guest graph can
grow arbitrarily large depending on the application. The results of this paper widen the class of computations that can be
performed on these product graphs which are often cited as being low‐cost alternatives for hypercubes.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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316.
This paper is concerned with health effects of the ash aerosol formed from the co-combustion of municipal sewage sludge (a CO2 neutral, ostensibly ‘green’ biomass fuel) with pulverized coal. To study, and mitigate, possible lung injury caused by inhalation of these ash particles, it is useful to employ ‘Health Effects Engineering’, which involves collaboration between combustion researchers and toxicologists. Health Effects Engineering attempts to build connections between mechanisms that form particulates during the combustion process and mechanisms that cause these ill health effects. By employing the methods of Health Effects Engineering, one can determine not only which fuel attributes are likely to contribute to lung injury, but also how tendencies of the ash to cause lung injury can be engineered out of the combustion process.Initial results showed that inhalation of ash from the co-combustion of municipal sewage sludge (MSS) and pulverized coal caused much greater lung damage in mice, as measured by lung permeability increase, than that of coal ash, or MSS ash, alone. MSS contains substantial quantities of zinc but little sulfur, while coal contains sulfur but little zinc. Therefore, systematic experiments were conducted to determine the health effects of combustion generated zinc particles and zinc plus sulfur particles. Zinc without sulfur led to ‘normal’ behavior as far as lung permeability was concerned. Zinc with sulfur added led to the ‘abnormal’ behavior noted also in the coal+MSS experiments. Therefore, the bad actor was identified to be zinc together with sulfur, and that was why the co-combustion of coal and MSS caused greater lung injury than the combustion of either fuel alone. Health effects engineering can also be employed to diminish this health risk caused by burning fuels containing both zinc and sulfur. Injection of a kaolinite sorbent downstream of the flame, but above the Zn dew point, can sequester the Zn, and react it to form a new species which was shown to be relatively benign. 相似文献
317.
Patricia Córdoba Raquel Ochoa-Gonzalez Oriol Font Maria Izquierdo Xavier Querol Carlos Leiva Maria Antonia López-Antón Mercedes Díaz-Somoano M. Rosa Martinez-Tarazona Constantino Fernandez Alfredo Tomás 《Fuel》2012,92(1):145-157
The abatement capacity of trace inorganic elements was studied in a large Pulverized Coal Combustion (PCC) power plant equipped with a wet limestone Flue Gas Desulphurisation (FGD) system. High proportions of most elements were retained as fly ash as consequence of the efficiency of the electrostatic precipitator (ESP, 99.6% of fly ash) and slag (11%). The most volatile elements, such as S and F are retained by the FGD gypsum, and Cl by the filtered water; whereas the moderately volatile elements, As and B, are retained mainly by fly ash, reaching very high abatement efficiencies for these elements when considering the whole plant (>92%). Selenium and Hg are still retained by the whole system with relatively high proportions (89% and 67%); however a prominently proportion is emitted; Se (11%) and Hg (29%), attaining gaseous/PM rate at the emissions reaching 0.08 and 290, respectively. The gaseous emissions are below the limits according to the European directive 2001/80/EC for large combustion plants and the PRTR threshold values with the exception of Hg emissions and particulate Se, As, Zn, Cu, Ni, and Cr. Remediation actions to prevent and/or reduce the gaseous and PM emissions as well as the determination of leachable potential of trace inorganic pollutants retained in FGD gypsum, especially F in view of its disposal, are of significant relevance. 相似文献
318.
319.
M.F.S.F. de Moura M.V.C. Fernandez R.D.S.G. Campilho 《Engineering Fracture Mechanics》2009,76(4):469-478
A detailed numerical analysis of the Edge Crack Torsion test was performed to verify its adequacy for the mode III interlaminar fracture characterization of composite laminates. A new data reduction scheme based on specimen compliance was proposed. Three-dimensional finite element analyses including a cohesive damage model were performed in order to evaluate the accuracy of perceived GIIIc values obtained with the proposed method. Despite some degree of crack length dependency of perceived GIIIc, acceptable errors could be achieved within a certain crack length range, which is thus recommended for experimental tests. 相似文献
320.
Mercedes Argüello Casteleiro Julio Des Maria Jesus Fernandez Prieto Rogelio Perez Hilary Paniagua 《Knowledge》2009,22(7):545-551
There is still a lack of full integration between current Electronic Health Records (EHRs) and medical guidelines that encapsulate evidence-based medicine. Thus, general practitioners (GPs) and specialised physicians still have to read document-based medical guidelines and decide among various options for managing common non-life-threatening conditions where the selection of the most appropriate therapeutic option for each individual patient can be a difficult task. This paper presents a simulation framework and computational test-bed, called V.A.F. Framework, for supporting simulations of clinical situations that boosted the integration between Health Level Seven (HL7) and Semantic Web technologies (OWL, SWRL, and OWL-S) to achieve content layer interoperability between online clinical cases and medical guidelines, and therefore, it proves that higher integration between EHRs and evidence-based medicine can be accomplished which could lead to a next generation of healthcare systems that provide more support to physicians and increase patients’ safety. 相似文献