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991.
992.
A. H. Edmiston 《BT Technology Journal》2007,25(1):68-78
Operational risk management is a reflection of the need for enterprises to demonstrate that they are prepared for all eventualities,
through monitoring day-to-day operational risks.
IT is an area that is critical to modern enterprises and consequently carries with it the capacity to cripple those same enterprises
— business disruption as a result of IT failure is a major area of operational risk. Modern IT in many enterprises, especially
large ones such as BT, is distributed and heterogeneous. This presents challenges to collecting and correlating management,
monitoring and audit data in a timely manner. It also highlights the need to take an end-to-end view, with data collected
from a number of sources and presented as an integrated picture of the health of a business solution. In an eBusiness environment,
there is also a need to manage, monitor and audit the IT interfaces with customers, suppliers and partners.
This paper looks at operational risk in an IT context and provides an overview of the contribution made by systems and applications
monitoring to successful operational risk management. This paper has concentrated on using monitoring to address the downside
of risk and reflects a culture in many organisations to eliminate or minimise risk. However, risk has an upside whereby an
enterprise can gain competitive advantage through ‘right setting’ risk tolerance — this advantage can only be gained when
the organisation begins to understand and articulates its risk appetite. Monitoring can contribute significantly to the upside
through supplying the information required to manage and control the risk exposure to perform within the accepted risk appetite,
facilitate risk taking and imbue a better risk culture in the organisation. 相似文献
993.
V. D. Belik R. V. Litvin M. S. Koval’chenko 《Powder Metallurgy and Metal Ceramics》2006,45(11-12):593-598
The influence exerted by electric-spark spraying on the kinetics of mass transfer and the physicomechanical properties of coatings is investigated. It is shown that electric-spark spraying is determined by the dynamic properties of the cathode jets, which depend on the electrical parameters of the spark discharge, the size of the interelectrode interval, and the physical properties of the coatings, which vary during spraying. 相似文献
994.
Fouling is a major problem in membrane processes of water treatment. It can be caused by the deposition of inorganic and organic particulate material, and of microbial cells which may subsequently form biofilms. In practice, usually more than one foulant participates in the formation of membrane deposits. Knowledge of the composition of fouling layers is important for the development of appropriate countermeasures. For this purpose, an experimental system was established for the generation and microscopic visualisation of mixed deposits, using fluorescently labelled model foulants: (i) drinking-water bacteria stained with nucleic acid-specific dyes (biofouling), (ii) synthetic clay mineral laponite stained with rhodamine 6G (inorganic particle fouling), and (iii) fluorescently labelled polystyrene microspheres (organic particle fouling). Polycarbonate and polyethersulfone membranes were challenged with these foulants by dead-end filtration. On the basis of different fluorescent labels, the single foulants in these mixed deposits could be visualised separately by confocal laser scanning microscopy which, in combination with image analysis, allowed the generation of three-dimensional views of the complete deposits. This method offers the possibility for the estimation of quantitative surface coverage by foulants and for the determination of the efficacy of cleaning measures with respect to the removal of different foulants. 相似文献
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A Saccharomyces cerevisiae sequence cloned by serendipity was found to encode a protein that is a new member of the Ypt/Rab monomeric G-protein family. This sequence shows high homology to the yeast genes SEC4 and YPT1 and, like SEC4 and YPT1, is essential for viability. The sequence was localized to chromosome V based upon hybridization to pulse-field gel-separated yeast chromosomes. The sequence has been deposited in the GenBank data library under Accession Number L17070. 相似文献
1000.
Numerical Simulation of the Fibre-Motion during the Extrusion of Short-Fibre-Reinforced Glass-Melts Fibre-reinforced materials are characterized by an anisotropic behaviour of the mechanical properties, which is caused by the alignment of the embedded fibres. In the case of short-fibre-compounds this behaviour is strongly influenced by the mechanism of flow during the manufacturing process. Numerical simulation Methods are preferentially used to get informations about the orientation of the reinforced fibres at the end of the molding-process and to improve the properties of the compound. For that, a model is developed, which calculates the motion of the short-fibres in the area of flow, basing on a three-dimensional finite-element-computation. Thereby the interaction between the Particular fibres during the orientation process is considered by using an interaction coefficient. Examplified at the extrusion of short fibre reinforced glass-melts, the fibre orientation is determined at models with different geometries of the pressing tool and variable boundary conditions. This procedure allows to determine the influence of the process-parameters On the expected quality of the composite. The represented simulation-model can also be used for other molding- and extrusion-processes of fibre reinforced materials. 相似文献