Papers by Jonathan Pearce
Energy Procedia, 2013
EU Member States are in the process of transposing European regulatory requirements that define t... more EU Member States are in the process of transposing European regulatory requirements that define the high-level conditions of a storage permit into their national laws. This regulatory framework defines a range of performance standards which recognise specific high-level uncertainties and long-term issues which storage developers will have to address. However, with one or two notable exceptions, the level of site characterisation required to obtain a storage permit has not been systematically evaluated. To determine the required geological site characterisation necessary to demonstrate adequate understanding of site performance, two storage case studies identify those issues that might remain challenging in the permitting process. These case studies, an onshore aquifer and an offshore multi-store site, produce credible dry-run storage permit applications from site geological characterisation activities, which are evaluated by a separate team, acting as a regulator. The applications, though necessarily reduced in scope from those anticipated for full storage projects, comprise the key elements of a permit. Issues identified during this process include: Defining the storage complex boundaries, which for certain sites may be challenging, especially where expected pressure responses may extend for some distance or where lateral boundaries may not be clearly defined. We present examples of how these regulatory boundaries have been defined for the two case studies. Key Performance Indicators (KPIs) include a range of metrics against which site performance can be measured, both during the operational and closure phases, providing a basis for the design of the geological monitoring program and the corrective measures plan.-specific KPIs in the case studies described. Whilst it might be relatively straightforward to define qualitative indicators, we conclude that KPIs will need to be defined quantitatively for them to be the most effective.
Measurement and Control
A pan-European project aimed at enhancing process efficiency through improved temperature measure... more A pan-European project aimed at enhancing process efficiency through improved temperature measurement (EMPRESS) is described. The project is aimed at solving a suite of specific, documented problems in high-value manufacturing industry through improved temperature metrology for process control. A key aspect is the introduction of traceability to the International Temperature Scale of 1990 in process. This involves a concerted effort across Europe to improve existing sensing techniques such as thermocouples and fibre-optic based pyrometry, as well as introduction of completely new techniques including phosphor thermometry and combustion thermometry. Each activity in the project is characterised by the involvement of an end-user in industry, and there are opportunities for joining the Stakeholder Community associated with the project.
Johnson Matthey Technology Review
It is known that Pt-Rh thermocouples exhibit mass loss when in the presence of oxygen at high tem... more It is known that Pt-Rh thermocouples exhibit mass loss when in the presence of oxygen at high temperatures due to the formation of volatile oxides of Pt and Rh. The mass losses of Pt, Pt-6%Rh and Pt-30%Rh wires, commonly used for thermocouples, were considered in this paper to characterise the mass loss of wires of the three compositions due to formation and evaporation of the oxides PtO2 and RhO2 under the conditions that would be seen by thermocouples used at high temperature. For the tests, the wires were placed in thin alumina tubes to emulate the thermocouple format, and the measurements were performed in air at a temperature of 1324 °C, i.e. with oxygen partial pressure of 21.3 kPa. It was found that the mass loss of the three wires increases linearly with elapsed time, consistent with other investigations, up to an elapsed time of about 150 hours, but after that, a marked acceleration of the mass loss is observed. Remarkably, previous high precision studies have shown that a ...
Explorations in Ethnic Studies
Proceedings of the Yorkshire Geological Society
Proceedings of the Ocean Drilling Program
Relationships between downhole resistivity/velocity logs and porosity styles, controlled by cemen... more Relationships between downhole resistivity/velocity logs and porosity styles, controlled by cementation/dissolution/recrystallization, are investigated using core and downhole logging data from the carbonate-rich sediments encountered during Leg 133 of the Ocean Drilling Program (ODP), northeastern Australia off the Great Barrier Reef. It is shown that although resistivity and velocity are controlled by porosity, the "connectiveness" of the solid phase (velocity) and fluid phase (resistivity) may be more important controls than porosity in these environments. Velocity logs in this environment are shown to be controlled primarily by the bulk properties of the solid fraction and fluid phases, with interparticle cementation causing significant increases in velocity during lithification. Downhole electrical resistivity logs, in contrast to velocity logs, are shown to respond to the fluid phase in these marine carbonate sediments, where the terrigenous clay fraction is small. Resistivity is shown to be dependent on the connectivity of the pore space in addition to its bulk porosity. The Archie m exponent (derived from resistivity and porosity) is shown (1) to increase to values above 3 when poorly connected vuggy or moldic styles dominate porosity and (2) to be independent of the strength of interparticle cements. Velocity and resistivity log responses are compared in different diagenetic carbonate environments. The effects of diagenetic processes in shallow-water reefal carbonates are contrasted with the effects of the normal compaction/lithification depth profile in carbonate-rich hemipelagic sediments. Signatures are identified in velocity/resistivity responses that are diagnostic of different diagenetically controlled porosity styles. For example, log responses from well-connected porosity developed in a dolomite, are distinguished from that in sediments having similar porosity, but extensive recrystallization, which may block the pore throats. A dimensionless velocity/resistivity ratio (VR) is proposed to quantify and to enhance the identification of cementation/dissolution/connectivity styles. A theoretical model is proposed that will predict the velocity vs. resistivity (and hence VR) relationships attributed to these different porosity styles. Within a lithified rock, a high VR ratio is shown to represent well-connected porosity, whereas a low VR ratio is shown to represent poorly connected porosity where the pore throats are blocked. This VR ratio is used to identify two substantially different trends within two Miocene reef units identified at Site 816 (Davies, McKenzie, Palmer-Julson, et al., 1991). Davies, McKenzie, Palmer-Julson, et al. (1991) and Pigram et al. (this volume) showed that there is evidence of subaerial exposure and fresh water diagenesis within both these reef units. We observed a trend of increasing fabric destruction with depth within the deeper Miocene reef unit at Site 816. Although dolomitization is complete within this unit, matrix recrystalization is seen to increase with depth. We postulate that recrystallization (where the matrix is now composed of dolomite rhombs having an open intercrystalline porosity) has lead to the generation of connected porosity at Site 816 that is seen as high values of the VR ratio. Thin layers having very high VR ratios were identified in the lower unit. One such layer was studied in more detail using formation microscanner (FMS) images. This 0.6-m-thick layer of distinctly lower resistivity has an internal structure that suggests that this may be a solution feature and might constitute a significant pathway for fluid flow in the formation.
International Journal of Thermophysics
Le Journal de Physique Colloques
AI Magazine
In many cooperative multiagent domains, the effect of local interactions between agents can be co... more In many cooperative multiagent domains, the effect of local interactions between agents can be compactly represented as a network structure. Given that agents are spread across such a network, agents directly interact only with a small group of neighbors. A distributed constraint optimization problem (DCOP) is a useful framework to reason about such networks of agents. Given agents’ inability to communicate and collaborate in large groups in such networks, we focus on an approach called k-optimality for solving DCOPs. In this approach, agents form groups of one or more agents until no group of k or fewer agents can possibly improve the DCOP solution; we define this type of local optimum, and any algorithm guaranteed to reach such a local optimum, as k-optimal. The article provides an overview of three key results related to koptimality. The first set of results gives worst-case guarantees on the solution quality of k-optima in a DCOP. These guarantees can help determine an appropria...
ESMO open, 2016
In this implementation phase of the European Cancer Patient's Bill of Rights (BoR), we confir... more In this implementation phase of the European Cancer Patient's Bill of Rights (BoR), we confirm the following three patient-centred principles that underpin this initiative:The right of every European citizen to receive the most accurate information and to be proactively involved in his/her care.The right of every European citizen to optimal and timely access to a diagnosis and to appropriate specialised care, underpinned by research and innovation.The right of every European citizen to receive care in health systems that ensure the best possible cancer prevention, the earliest possible diagnosis of their cancer, improved outcomes, patient rehabilitation, best quality of life and affordable health care. The key aspects of working towards implementing the BoR are:Agree our high-level goal. The vision of 70% long-term survival for patients with cancer in 2035, promoting cancer prevention and cancer control and the associated progress in ensuring good patient experience and quality ...
Metallurgical and Materials Transactions B, 2016
Jim. (2016) MTDATA and the prediction of phase equilibria in oxide systems : 30 years of industri... more Jim. (2016) MTDATA and the prediction of phase equilibria in oxide systems : 30 years of industrial collaboration. Metallurgical and Materials Transactions B.
Proceedings of the Fourth International Joint Conference on Autonomous Agents and Multiagent Systems, 2005
For agents deployed in real-world settings, such as businesses, universities and research laborat... more For agents deployed in real-world settings, such as businesses, universities and research laboratories, it is critical that agents protect their individual users' privacy when interacting with others entities. Indeed, privacy is recognized as a key motivating factor in design of several multiagent algorithms, such as distributed constraint optimization (DCOP) algorithms. Unfortunately, rigorous and general quantitative metrics for analysis and comparison of such multiagent algorithms with respect to privacy loss are lacking. This paper takes a key step towards developing a general quantitative model from which one can analyze and generate metrics of privacy loss by introducing the VPS (Valuations of Possible States) framework. VPS is shown to capture various existing measures of privacy created for specific domains of distributed constraint satisfactions problems (DCSPs). The utility of VPS is further illustrated via analysis of DCOP algorithms, when such algorithms are used by personal assistant agents to schedule meetings among users. In addition, VPS allows us to quantitatively evaluate the properties of several privacy metrics generated through qualitative notions. We obtain the unexpected result that decentralization does not automatically guarantee superior protection of privacy.
Aps Meeting Abstracts, Mar 1, 2008
We present neutron-scattering measurements of the atomic momentum distribution and its Fourier tr... more We present neutron-scattering measurements of the atomic momentum distribution and its Fourier transform, the one-body density matrix ͑OBDM͒, in liquid 4 He films adsorbed in nanoporous MCM-41. The measurements were performed at liquid 4 He temperatures T = 0.3 K and T = 2.3 K and saturated vapor pressure ͑SVP͒ as a function of filling of the MCM-41. The chief goal is to determine whether the OBDM of nearly twodimensional ͑2D͒ helium films has a tail at low temperatures and to measure the height of the tail. It is also to investigate the 2D-3D crossover and whether the height of the tail is larger in 2D than in 3D as predicted. We are able to determine the tail height at short distances only. In the thinnest films investigated ͑approximately half of a liquid 4 He monolayer͒, we find clear evidence of a tail at T = 0.3 K of height n 0 = ͑9.34Ϯ 3.84͒% that is not there at T = 2.3 K. The tail height, denoted as n 0 , decreases with filling to n 0 = ͑2.45Ϯ 2.54͒% near full pore filling ͑nearly 3D͒. The tail height is larger in 2D than in 3D as predicted although the absolute values are smaller than predicted for bulk 2D and 3D. In 3D, n 0 is the condensate fraction.
Healthcare Financial Management Journal of the Healthcare Financial Management Association, Jul 1, 2012
To succeed under population-based health care, organizations need to understand thoroughly how th... more To succeed under population-based health care, organizations need to understand thoroughly how this approach differs from traditional fee-for-service health care. To manage care under capitation, the contracting organization should have a population of sufficient size and a clear means of assigning patients to that population. To assess performance, the organization requires metrics that view performance in terms of per member per month, while avoiding common pitfalls of misapplying such metrics.
Eprint Arxiv Cond Mat 0609529, Sep 20, 2006
We present neutron scattering measurements of the momentum distribution of liquid 3 He-4 He mixtu... more We present neutron scattering measurements of the momentum distribution of liquid 3 He-4 He mixtures. The experiments were performed at wavevectors Q, 26 ≤ Q ≤ 29Å −1 , on the MARI timeof-flight spectrometer at the ISIS Facility, Rutherford Appleton Laboratory, a spallation neutron source. Mixtures with 3 He concentrations x between 0 and 20% were investigated both in the superfluid and normal phases. From the data, we extract the Bose-Einstein condensate fraction n0 and the momentum distributions of 3 He and 4 He atoms. We find that n0 increases somewhat above the pure 4 He value when 3 He is added; e.g from n0 = (7.25 ± 0.75)% at x = 0 to (11 ± 3)% at x = 15-20%. This agrees with predictions but is less than the only previous measurement. We find a 4 He kinetic energy K4 for pure 4 He that agrees with previous determinations. K4 decreases somewhat with increasing 3 He concentration, less than observed previously and found in early calculations but in agreement with a more recent Monte Carlo calculation. The 3 He response is not well reproduced by a Fermi gas momentum distribution, n(k). Rather an n(k) having a small step height at the Fermi surface and a substantial high momentum tail characteristic of a strongly interacting Fermi liquid provides a good fit. This n(k) is consistent with calculated n(k). Thus agreement between theory and experiment is obtained comparing n(k) in contrast to earlier findings based on comparing calculated and observed 3 He kinetic energies.
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Papers by Jonathan Pearce