Impact of electric vehicles on GB electricity demand and associated benefits for system control

This paper investigates the impact that electric vehicle uptake will have on the national electricity demand of Great Britain. Data from the National Travel Survey, and the Coventry and Birmingham Low Emissions Demonstration (CABLED) are used to model an electrical demand profile in a future scenario of significant electric vehicle market penetration. These two methods allow comparison of how conventional cars are currently used, and the resulting electrical demand with simple substitution of energy source, with data showing how electric vehicles are actually being used at present. The report finds that electric vehicles are unlikely to significantly impact electricity demand in GB. The paper also aims to determine whether electric vehicles have the potential to provide ancillary services to the grid operator, and if so, the capacity for such services that would be available. Demand side management, frequency response and Short term Operating Reserve (STOR) are the services considered. The report finds that electric cars are unlikely to provide enough moveable demand peak shedding to be worthwhile. However, it is found that controlling vehicle charging would provide sufficient power control to viably act as frequency response for dispatch by the transmission system operator. This paper concludes that electric vehicles have technical potential to aid management of the transmission network without adding a significant demand burden. © 2013 IEEE.

Modulation of network oscillatory activity and GABAergic synaptic transmission by CB1 cannabinoid receptors in the rat medial entorhinal cortex

Cannabinoids modulate inhibitory GABAergic neurotransmission in many brain regions. Within the temporal lobe, cannabinoid receptors are highly expressed, and are located presynaptically at inhibitory terminals. Here, we have explored the role of type-1 cannabinoid receptors (CB1Rs) at the level of inhibitory synaptic currents and field-recorded network oscillations. We report that arachidonylcyclopropylamide, an agonist at CB1R, inhibits GABAergic synaptic transmission onto both superficial and deep medial entorhinal (mEC) neurones, but this has little effect on network oscillations in beta/gamma frequency bands. By contrast, the CB1R antagonist/inverse agonist LY320135 (500?nM), increased GABAergic synaptic activity and beta/gamma oscillatory activity in superficial mEC, was suppressed, whilst that in deep mEC was enhanced. These data indicate that cannabinoid-mediated effects on inhibitory synaptic activity may be constitutively active in vitro, and that modulation of CB1R activation using inverse agonists unmasks complex effects of CBR function on network activity.

Developing a framework to evaluate business networks:the case of Ireland's industry-led network initiative

Business networks have been described as cooperative arrangements between independent business organisations that vary from contractual joint ventures to informal exchanges of information. This collaboration has become recognised as an innovative and efficient tool for organising interdependent activities, with benefits accruing to both firms and the local economy. For a number of years, resources have been devoted to supporting Irish networking policies. One recent example of such support is the Irish government's target of €20 million per annum for five years to support the creation of enterprise-led networks. It is imperative that a clear rationale for such interventions is established, as the opportunity cost of public funds is high. This article, therefore, develops an evaluation framework for such networking interventions. This framework will facilitate effective programme planning, implementation and evaluation. It will potentially show how a chain of cause-and-effect at both micro and macro-levels for networking interventions can be established.

The missing ingredient:inter-municipal cooperation and central-local relations in the UK

The thrust of the argument presented in this chapter is that inter-municipal cooperation (IMC) in the United Kingdom reflects local government's constitutional position and its exposure to the exigencies of Westminster (elected central government) and Whitehall (centre of the professional civil service that services central government). For the most part councils are without general powers of competence and are restricted in what they can do by Parliament. This suggests that the capacity for locally driven IMC is restricted and operates principally within a framework constructed by central government's policy objectives and legislation and the political expediencies of the governing political party. In practice, however, recent examples of IMC demonstrate that the practices are more complex than this initial analysis suggests. Central government may exert top-down pressures and impose hierarchical directives, but there are important countervailing forces. Constitutional changes in Scotland and Wales have shifted the locus of central- local relations away from Westminster and Whitehall. In England, the seeding of English government regional offices in 1994 has evolved into an important structural arrangement that encourages councils to work together. Within the local government community there is now widespread acknowledgement that to achieve the ambitious targets set by central government, councils are, by necessity, bound to cooperate and work with other agencies. In recent years, the fragmentation of public service delivery has affected the scope of IMC. Elected local government in the UK is now only one piece of a complex jigsaw of agencies that provides services to the public; whether it is with non-elected bodies, such as health authorities, public protection authorities (police and fire), voluntary nonprofit organisations or for-profit bodies, councils are expected to cooperate widely with agencies in their localities. Indeed, for projects such as regeneration and community renewal, councils may act as the coordinating agency but the success of such projects is measured by collaboration and partnership working (Davies 2002). To place these developments in context, IMC is an example of how, in spite of the fragmentation of traditional forms of government, councils work with other public service agencies and other councils through the medium of interagency partnerships, collaboration between organisations and a mixed economy of service providers. Such an analysis suggests that, following changes to the system of local government, contemporary forms of IMC are less dependent on vertical arrangements (top-down direction from central government) as they are replaced by horizontal modes (expansion of networks and partnership arrangements). Evidence suggests, however that central government continues to steer local authorities through the agency of inspectorates and regulatory bodies, and through policy initiatives, such as local strategic partnerships and local area agreements (Kelly 2006), thus questioning whether, in the case of UK local government, the shift from hierarchy to network and market solutions is less differentiated and transformation less complete than some literature suggests. Vertical or horizontal pressures may promote IMC, yet similar drivers may deter collaboration between local authorities. An example of negative vertical pressure was central government's change of the systems of local taxation during the 1980s. The new taxation regime replaced a tax on property with a tax on individual residency. Although the community charge lasted only a few years, it was a highpoint of the then Conservative government policy that encouraged councils to compete with each other on the basis of the level of local taxation. In practice, however, the complexity of local government funding in the UK rendered worthless any meaningful ambition of councils competing with each other, especially as central government granting to local authorities is predicated (however imperfectly) on at least notional equalisation between those areas with lower tax yields and the more prosperous locations. Horizontal pressures comprise factors such as planning decisions. Over the last quarter century, councils have competed on the granting of permission to out-of-town retail and leisure complexes, now recognised as detrimental to neighbouring authorities because economic forces prevail and local, independent shops are unable to compete with multiple companies. These examples illustrate tensions at the core of the UK polity of whether IMC is feasible when competition between local authorities heightened by local differences reduces opportunities for collaboration. An alternative perspective on IMC is to explore whether specific purposes or functions promote or restrict it. Whether in the principle areas of local government responsibilities relating to social welfare, development and maintenance of the local infrastructure or environmental matters, there are examples of IMC. But opportunities have diminished considerably as councils lost responsibility for services provision as a result of privatisation and transfer of powers to new government agencies or to central government. Over the last twenty years councils have lost their role in the provision of further-or higher-education, public transport and water/sewage. Councils have commissioning power but only a limited presence in providing housing needs, social care and waste management. In other words, as a result of central government policy, there are, in practice, currently far fewer opportunities for councils to cooperate. Since 1997, the New Labour government has promoted IMC through vertical drivers and the development; the operation of these policy initiatives is discussed following the framework of the editors. Current examples of IMC are notable for being driven by higher tiers of government, working with subordinate authorities in principal-agent relations. Collaboration between local authorities and intra-interand cross-sectoral partnerships are initiated by central government. In other words, IMC is shaped by hierarchical drivers from higher levels of government but, in practice, is locally varied and determined less by formula than by necessity and function. © 2007 Springer.

Limitations of the isolated GP-STN network

An in vitro mouse slice preparation from control and MPTP-treated mice in which functional reciprocal GP-STN connectivity is maintained, does not produce oscillatory bursting or synchronous activity neuronal activity. Pharmacological interventions that produce bursting activity do so without concomitant neuronal synchrony, or a requirement for glutamate or GABA transmission. Pre-treatment with MPTP did not alter this behaviour. Thus, we have no evidence that the functionally connected, but isolated, GP — STN network can act as a pacemaker for synchronous correlated activity in the basal ganglia and must conclude that other inputs such as those from cortex and/or striatum are required.

Numerical modelling of dispersion managed soliton transmission

This thesis presents the results of numerical modelling of the propagation of dispersion managed solitons. The theory of optical pulse propagation in single mode optical fibre is introduced specifically looking at the use of optical solitons for fibre communications. The numerical technique used to solve the nonlinear Schrödinger equation is also introduced. The recent developments in the use of dispersion managed solitons are reviewed before the numerical results are presented. The work in this thesis covers two main areas; (i) the use of a saturable absorber to control the propagation of dispersion managed solutions and (ii) the upgrade of the installed standard fibre network to higher data rates through the use of solitons and dispersion management. Saturable absorbe can be used to suppress the build up of noise and dispersive radiation in soliton transmission lines. The use of saturable absorbers in conjunction with dispersion management has been investigated both as a single pulse and for the transmission of a 10Gbit/s data pattern. It is found that this system supports a new regime of stable soliton pulses with significantly increased powers. The upgrade of the installed standard fibre network to higher data rates through the use of fibre amplifiers and dispersion management is of increasing interest. In this thesis the propagation of data at both 10Gbit/s and 40Gbit/s is studied. Propagation over transoceanic distances is shown to be possible for 10Gbit/s transmission and for more than 2000km at 40Gbit/s. The contribution of dispersion managed solitons in the future of optical communications is discussed in the thesis conclusions.

Numerical modelling of devices and advanced transmission schemes embracing Raman effect

This thesis presents a theoretical investigation on applications of Raman effect in optical fibre communication as well as the design and optimisation of various Raman based devices and transmission schemes. The techniques used are mainly based on numerical modelling. The results presented in this thesis are divided into three main parts. First, novel designs of Raman fibre lasers (RFLs) based on Phosphosilicate core fibre are analysed and optimised for efficiency by using a discrete power balance model. The designs include a two stage RFL based on Phosphosilicate core fibre for telecommunication applications, a composite RFL for the 1.6 μm spectral window, and a multiple output wavelength RFL aimed to be used as a compact pump source for fiat gain Raman amplifiers. The use of Phosphosilicate core fibre is proven to effectively reduce the design complexity and hence leads to a better efficiency, stability and potentially lower cost. Second, the generalised Raman amplified gain model approach based on the power balance analysis and direct numerical simulation is developed. The approach can be used to effectively simulate optical transmission systems with distributed Raman amplification. Last, the potential employment of a hybrid amplification scheme, which is a combination between a distributed Raman amplifier and Erbium doped amplifier, is investigated by using the generalised Raman amplified gain model. The analysis focuses on the use of the scheme to upgrade a standard fibre network to 40 Gb/s system.

Automatic control of attenuation in a digital communication network

This thesis describes the investigation of an adaptive method of attenuation control for digital speech signals in an analogue-digital environment and its effects on the transmission performance of a national telecommunication network. The first part gives the design of a digital automatic gain control, able to operate upon a P.C.M. signal in its companded form and whose operation is based upon the counting of peaks of the digital speech signal above certain threshold levels. A study was ma.de of a digital automatic gain control (d.a.g.c.) in open-loop configuration and closed-loop configuration. The former was adopted as the means for carrying out the automatic control of attenuation. It was simulated and tested, both objectively and subjectively. The final part is the assessment of the effects on telephone connections of a d.a.g.c. that introduces gains of 6 dB or 12 dB. This work used a Telephone Connection Assessment Model developed at The University of Aston in Birmingham. The subjective tests showed that the d.a.g.c. gives advantage for listeners when the speech level is very low. The benefit is not great when speech is only a little quieter than preferred. The assessment showed that, when a standard British Telecom earphone is used, insertion of gain is desirable if speech voltage across the earphone terminals is below an upper limit of -38 dBV. People commented upon the presence of an adaptive-like effect during the tests. This could be the reason why they voted against the insertion of gain at level only little quieter than preferred, when they may otherwise have judged it to be desirable. A telephone connection with a d.a.g.c. in has a degree of difficulty less than half of that without it. The score Excellent plus Good is 10-30% greater.

Digital video transmission over wireless networks

The advent of the Integrated Services Digital Network (ISDN) led to the standardisation of the first video codecs for interpersonal video communications, followed closely by the development of standards for the compression, storage and distribution of digital video in the PC environment, mainly targeted at CD-ROM storage. At the same time the second-generation digital wireless networks, and the third-generation networks being developed, have enough bandwidth to support digital video services. The radio propagation medium is a difficult environment in which to deploy low bit error rate, real time services such as video. The video coding standards designed for ISDN and storage applications, were targeted at low bit error rate levels, orders of magnitude lower than the typical bit error rates experienced on wireless networks. This thesis is concerned with the transmission of digital, compressed video over wireless networks. It investigates the behaviour of motion compensated, hybrid interframe DPCM/DCT video coding algorithms, which form the basis of current coding algorithms, in the presence of high bit error rates commonly found on digital wireless networks. A group of video codecs, based on the ITU-T H.261 standard, are developed which are robust to the burst errors experienced on radio channels. The radio link is simulated at low level, to generate typical error files that closely model real world situations, in a Rayleigh fading environment perturbed by co-channel interference, and on frequency selective channels which introduce inter symbol interference. Typical anti-multipath techniques, such as antenna diversity, are deployed to mitigate the effects of the channel. Link layer error control techniques are also investigated.

Stationary scattering from a nonlinear network

Transmission through a complex network of nonlinear one-dimensional leads is discussed by extending the stationary scattering theory on quantum graphs to the nonlinear regime. We show that the existence of cycles inside the graph leads to a large number of sharp resonances that dominate scattering. The latter resonances are then shown to be extremely sensitive to the nonlinearity and display multistability and hysteresis. This work provides a framework for the study of light propagation in complex optical networks.

Forecasting and risk analysis applied to management planning and control

The aim of this research was to improve the quantitative support to project planning and control principally through the use of more accurate forecasting for which new techniques were developed. This study arose from the observation that in most cases construction project forecasts were based on a methodology (c.1980) which relied on the DHSS cumulative cubic cost model and network based risk analysis (PERT). The former of these, in particular, imposes severe limitations which this study overcomes. Three areas of study were identified, namely growth curve forecasting, risk analysis and the interface of these quantitative techniques with project management. These fields have been used as a basis for the research programme. In order to give a sound basis for the research, industrial support was sought. This resulted in both the acquisition of cost profiles for a large number of projects and the opportunity to validate practical implementation. The outcome of this research project was deemed successful both in theory and practice. The new forecasting theory was shown to give major reductions in projection errors. The integration of the new predictive and risk analysis technologies with management principles, allowed the development of a viable software management aid which fills an acknowledged gap in current technology.

Effect of dopamine on synchronous neuronal oscillations in the globus pallidus-subthalamic nucleus network

Changes in the pattern of activity of neurones within the basal ganglia are relevant in the pathophysiology and symptoms of Parkinson’s disease. The globus pallidus (GP) – subthalamic nucleus (STN) network has been proposed to form a pacemaker driving regenerative synchronous bursting activity. In order to test whether this activity can be sustained in vitro a 20o parasagittal slice of mouse midbrain was developed which preserved functional connectivity between the STN and GP. Mouse STN and GP cells were characterised electrophysiologically by the presence or absence of a voltage sag in response to hyperpolarising current steps indicative of Ih and the presence of rebound depolarisations. The presence of evoked and spontaneous post-synaptic GABA and glutamatergic currents indicated functional connectivity between the STN and GP. In control slices, STN cells fired action potentials at a regular rate, activity which was unaffected by bath application of the GABAA receptor antagonist picrotoxin (50 μM) or the glutamate receptor antagonist CNQX (10 μM). Paired extracellular recordings of STN cells showed uncorrelated firing. Oscillatory burst activity was induced pharmacologically using the glutamate receptor agonist, NMDA (20 μM), in combination with the potassium channel blocker apamin (50 -100 nM). The burst activity was unaffected by bath application of picrotoxin or CNQX while paired STN recordings showed uncorrelated activity indicating that the activity is not produced by the neuronal network. Thus, no regenerative activity is evident in this mouse brain preparation, either in control slices or when bursting is pharmacologically induced, suggesting the requirement of other afferent inputs that are not present in the slice. Using single-unit extracellular recording, dopamine (30 μM) produced an excitation of STN cells. This excitation was independent of synaptic transmission and was mimicked by both the Dl-like receptor agonist SKF38393 (10 μM) and the D2-like receptor agonist quinpirole (10 μM). However, the excitation was partially reduced by the D1-like antagonist SCH23390 (2 μM) but not by the D2-like antagonists sulpiride (10 μM) and eticlopride (10 μM). Using whole-recordings, dopamine was shown to induce membrane depolarisation. This depolarisation was caused either by a D1-like receptor mediated increase in a conductance which reversed at -34 mV, consistent with a non-specific cation conductance, or a D2-like receptor mediated decrease in conductance which reversed around -100 mV, consistent with a potassium conductance. Bath application of dopamine altered the pattern of the burst-firing produced by NMDA an apamin towards a more regular pattern. This effect was associated with a decrease in amplitude and ll1crease in frequency of TTX-resistant plateau potentials which underlie the burst activity.

The pro-reform movement led by Avenir de la Francaise:a point of leverage in the French political process?

The study examines factors influencing language planning decisions in contemporary France. It focuses upon the period 1992-1994, which witnessed the introduction of two major language policy measures, the first an amendment to the French Constitution, in 1992, proclaiming the language of the Republic as French, the second, in 1994, legislation to extend the ambit of the loi Bas-Lauriol, governing the use of the French language in France. The thesis posits a significant role for the pro-reform movement led by the French language association Avenir de la Langue Francaise (ALF) in the introduction and formulation of the policy measures concerned. The movement is depicted as continuing the traditional pattern of intellectual involvement in language planning, whilst also marking the beginning of a highly proactive, and increasingly political approach. Detailed examination of the movement's activities reveals that contextual factors and strategic strength combined to facilitate access to the levers of power, and enabled those involved to exert an impact on policy initiation, formulation, and ultimately implementation. However, ALF's decision to pursue the legislative route led to the expansion of the network of actors involved in language policymaking, and the development of counter-pressure from sectoral groups. It is suggested that this more interventionist approach destabilised the traditionally consensual language policy community, and called into question the quasi-monopoly of the intelligentsia in respect of language policymaking. It raised broader questions relating to freedom of expression and the permissible limits of language regulation in a democracy such as France. It also exposed ongoing ambiguities and inconsistencies in the interpretation of the tenets of language planning.

Planning for cycling in the West Midlands

The issues involved in planning for pedal cyclists are examined with reference to the West Midlands County. Working with a local cycling campaign group, the researcher uses action research methods to investigate and influence the campaign. Development of cycle planning is traced through the literature, focusing on bicycle ownership, bicycle use and cycling policy. UK practice is contrasted with the integrated approach of other countries. An extensive bibliography is provided. Local authority cycle planning through the TPP process is systematically assessed over three years. This provides a context for the information regarding cycling in the West Midlands. Existing data is presented from the 1981 Census and local police road accident and bicycle theft records. The developing relationship between the local authority and the cycle campaign group is narrated in detail, explaining the problems that can beset efforts to improve conditions for cyclists. The researcher was closely involved in this interaction, particularly with policy and a major public inquiry. A survey of the Cycle Campaign Network indicates that the local group was not atypical. To provide information relevant to the local campaign and for effective local planning, a survey of 3,500 West Midlands residents was conducted using a novel combination of questionnaires and interviews. It shows that 1) Bicycle ownership and use is considerably higher than indicated by the 1978/9 National Travel Survey 2) Cycling is most import to certain disadvantaged sections of the community, particularly the young, those without access to a car and in the lower SEGs. The broader issues of transport policy are discussed, concluding that cycling is regarded as a marginal activity and that changes in general transport policy, land use planning and fiscal arrangements are necessary conditions for cycle planning to succeed. An integrated package of cycling measures involving engineering, education, enforcement and encouragement is also required. Recommendations are made concerning central government, local authorities and cycle campaign groups. Subjects for further research are identified.

OTDM network processing using all-optical and electro-optical devices

The current optical communications network consists of point-to-point optical transmission paths interconnected with relatively low-speed electronic switching and routing devices. As the demand for capacity increases, then higher speed electronic devices will become necessary. It is however hard to realise electronic chip-sets above 10 Gbit/s, and therefore to increase the achievable performance of the network, electro-optic and all-optic switching and routing architectures are being investigated. This thesis aims to provide a detailed experimental analysis of high-speed optical processing within an optical time division multiplexed (OTDM) network node. This includes the functions of demultiplexing, 'drop and insert' multiplexing, data regeneration, and clock recovery. It examines the possibilities of combining these tasks using a single device. Two optical switching technologies are explored. The first is an all-optical device known as 'semiconductor optical amplifier-based nonlinear optical loop mirror' (SOA-NOLM). Switching is achieved by using an intense 'control' pulse to induce a phase shift in a low-intensity signal propagating through an interferometer. Simultaneous demultiplexing, data regeneration and clock recovery are demonstrated for the first time using a single SOA-NOLM. The second device is an electroabsorption (EA) modulator, which until this thesis had been used in a uni-directional configuration to achieve picosecond pulse generation, data encoding, demultiplexing, and 'drop and insert' multiplexing. This thesis presents results on the use of an EA modulator in a novel bi-directional configuration. Two independent channels are demultiplexed from a high-speed OTDM data stream using a single device. Simultaneous demultiplexing with stable, ultra-low jitter clock recovery is demonstrated, and then used in a self-contained 40 Gbit/s 'drop and insert' node. Finally, a 10 GHz source is analysed that exploits the EA modulator bi-directionality to increase the pulse extinction ratio to a level where it could be used in an 80 Gbit/s OTDM network.