The Use of a Waste Conversion Index as a Long Term Performance Indicator for Civil Nuclear Laibilities

In November 2001 the UK Government issued a statement on the future management of public sector nuclear liabilities and in its white paper “Managing the nuclear legacy” proposed the establishment of a Liabilities Management Authority, or the Nuclear Decommissioning Authority (NDA) as it is now called. With the advent of the NDA, whose aim will be to safely and cost effectively reduce nuclear liabilities, and existing Government Policy which requires systematic and progressive reduction in hazard, there is a need for some form of index to demonstrate progress. Although there are many indices in use, mainly within the chemical industry, none of these are considered suitable for this purpose. A Waste Conversion Index is currently being developed to satisfy these needs. The Waste Conversion Index will reflect an emphasis on passive safety rather than the more traditional safety analysis which focuses on risk. It is intended to be applicable across all UK civil nuclear sites and may act as one of a number of long-term performance indicators. This paper describes how the index is formulated, and the various factors used in the calculation together with its main uses including its use as a predictive tool to demonstrate progressive hazard reduction as nuclear liabilities are reduced. In addition the paper warns against the misuse of the index as a sole means of decision making in developing hazard reduction strategies, prioritising projects and allocating funding. Finally, some examples are given of its application to existing facilities.

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Intelligent long-term performance analysis in power electronics systems

Scientific Reports ◽

10.1038/s41598-021-87165-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Saeed Peyghami ◽

Tomislav Dragicevic ◽

Frede Blaabjerg

Keyword(s):

Performance Indicator ◽

Thermal Characteristics ◽

Operating Conditions ◽

System Level ◽

Power Electronic ◽

Reliability Modeling ◽

Artificial Neural Network Ann ◽

Long Term Performance ◽

Term Performance

AbstractThis paper proposes a long-term performance indicator for power electronic converters based on their reliability. The converter reliability is represented by the proposed constant lifetime curves, which have been developed using Artificial Neural Network (ANN) under different operating conditions. Unlike the state-of-the-art theoretical reliability modeling approaches, which employ detailed electro-thermal characteristics and lifetime models of converter components, the proposed method provides a nonparametric surrogate model of the converter based on limited non-linear data from theoretical reliability analysis. The proposed approach can quickly predict the converter lifetime under given operating conditions without a further need for extended, time-consuming electro-thermal analysis. Moreover, the proposed lifetime curves can present the long-term performance of converters facilitating optimal system-level design for reliability, reliable operation and maintenance planning in power electronic systems. Numerical case studies evaluate the effectiveness of the proposed reliability modeling approach.

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Intelligent Long-Term Performance Analysis in Power Electronics Systems

10.21203/rs.3.rs-133446/v1 ◽

2020 ◽

Author(s):

Saeed Peyghami ◽

Tomislav Dragicevic ◽

Frede Blaabjerg

Keyword(s):

Performance Indicator ◽

Thermal Characteristics ◽

Operating Conditions ◽

System Level ◽

Power Electronic ◽

Reliability Modeling ◽

Artificial Neural Network Ann ◽

Long Term Performance ◽

Term Performance

Abstract This paper proposes a long-term performance indicator for power electronic converters based on their reliability. The converter reliability is represented by the proposed constant lifetime curves, which have been developed using Artificial Neural Network (ANN) under different operating conditions. Unlike the state-of-the-art theoretical reliability modeling approaches, which employ detailed electro-thermal characteristics and lifetime models of converter components, the proposed method provides a nonparametric surrogate model of the converter based on limited non-linear data from theoretical reliability analysis. The proposed approach can quickly predict the converter lifetime under given operating conditions without a further need for extended, time-consuming electro-thermal analysis. Moreover, the proposed lifetime curves can present the long-term performance of converters facilitating optimal system-level design for reliability, reliable operation and maintenance planning in power electronic systems. Numerical case studies evaluate the effectiveness of the proposed reliability modeling approach.

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Hazardous and radioactive waste management: a case of dual standards?

Geological Society London Engineering Geology Special Publications ◽

10.1144/gsl.eng.1987.004.01.59 ◽

1987 ◽

Vol 4 (1) ◽

pp. 489-494

Author(s):

N. A. Chapman ◽

G. M. Williams

Keyword(s):

Site Investigation ◽

Nuclear Industry ◽

Similar Amount ◽

Toxic Wastes ◽

Recent Activity ◽

The Uk ◽

Long Term Performance ◽

Term Performance ◽

Landfill Disposal

AbstractThe recent activity by the UK Nuclear industry to investigate the safety of sites in shallow ground for the disposal of low level radioactive wastes has not surprisingly prompted comparison with landfill facilities in which toxic wastes are being deposited. The conclusion is that the level of site investigation, operation and long term performance assessment proposed for the radwaste sites is many orders of magnitude greater than that required by the regulatory authorities for landfills where the operators responsibility for the safety of the site virtually disappears once the last load of waste is tipped and the disposal licence lapses. Furthermore, the research budget for radwaste exceeds that for landfill disposal by a similar amount even though the risk from radwaste can be shown to be many times less than that from toxic wastes. Since the same government department is in charge of radwaste and landfill disposal, it seems that dual standards are operating, and that either the radwaste managers are being singled out for unfair scrutiny, or that insufficient attention is being directed at the real threat to the environment from 'antediluvian and ramshackle' landfill practices.

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Genotype by nutrition interactions from Langhill dairy cows in three lactations

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200003550 ◽

1999 ◽

Vol 1999 ◽

pp. 200-200

Author(s):

J.E. Pryce ◽

G. Simm ◽

R.F. Veerkamp ◽

J.D. Oldham

Keyword(s):

Reproductive Performance ◽

Research Centre ◽

Feeding System ◽

Initial Report ◽

Holstein Friesian ◽

The Uk ◽

Long Term Performance ◽

Term Performance ◽

Friesian Cows

The economic pressures on the dairy industry may force more farmers to consider reducing the amount of concentrates fed to cows in order to keep costs down. We have been testing whether the long-term performance of daughters of sires progeny tested in high concentrate systems maintain their advantage over cows of average genetic merit when managed in a lower input feeding system. This paper extends the scope of our initial report (Chalmers et al., 1997) and includes data on reproductive performance.Data were from Holstein-Friesian cows managed at the Langhill Dairy Cattle Research Centre. Sires of the Selection (S) line are among the highest available in the UK for predicted transmitting abilities of weight of fat plus protein (PTA F+P). Sires of Control (C) line cows are about UK average for PTA F+P.

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